diff --git a/pages/๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ.md b/pages/๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ.md index 87c438d..e1dfcea 100644 --- a/pages/๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ.md +++ b/pages/๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ.md @@ -1,501 +1,34 @@ deck:: Logseq/coding tip -- ## **๊ฐ ์–ธ์–ด๋ณ„ 2์ฐจ์› ๋ฐฐ์—ด(n*m) ์ƒ์„ฑ** - - **Javascript** - - id:: 684578c3-84af-4595-af7a-dc46f58bd99b - 1. ํ•œ์ค„๋กœ ์„ ์–ธํ•˜๊ธฐ(2๊ฐ€์ง€ ๋ฐฉ๋ฒ•) #card +- ## **Javascript / Typescript** + - ### **์ด์ฐจ์› ๋ฐฐ์—ด(n*m) ์ƒ์„ฑ** + - id:: 6867f897-928a-4f22-8184-491fa70314db + 1. Array.from() ์‚ฌ์šฉ๋ฒ• #card + - ```javascript + const arr = Array.from({length : n}, () => new Array(m).fill(0)); + ``` + - id:: 6867f8fc-3249-4ced-91aa-a2c951c11b0b + 2. Array().fill() ์‚ฌ์šฉ๋ฒ• #card - ```javascript - const arr = Array.from({ length: n }, () => new Array(m).fill(0)); - const arr = new Array(n).fill().map(() => new Array(m).fill(0)); ``` - - id:: 68457909-49bf-4cab-b5fc-c61081c0aa0c - 2. ๋ฐ˜๋ณต๋ฌธ์œผ๋กœ ์ค‘์ฒฉํ•ด์„œ ์ƒ์„ฑํ•˜๊ธฐ #card + - id:: 6867f8fe-39c6-438b-a045-4f8687ad0b1d + 3. ๋ฐ˜๋ณต๋ฌธ ์ˆœํšŒ #card - ```javascript let arr = []; - for (let i = 0; i < n; i++) { + for(int i=0; i - id:: 68500a89-08d4-48b2-aa6b-c465041f065b - **๋ฐฐ์—ด์˜ ๋ชจ๋“  ์š”์†Œ๊ฐ€ ์กฐ๊ฑด์‹์„ ๋งŒ์กฑํ•˜๋Š”์ง€ ํ™•์ธํ•ด์„œ T/F๋ฅผ ๋ฐ˜ํ™˜ํ•˜๋Š” ๋งค์„œ๋“œ** - ```javascript - const arr = [1,2,3,4,5]; - arr.every((element, index, array) => {์กฐ๊ฑด์‹}); - // element: ํ˜„์žฌ ์š”์†Œ - // index: ํ˜„์žฌ ์ธ๋ฑ์Šค (์ƒ๋žต ๊ฐ€๋Šฅ) - // array: ์›๋ณธ ๋ฐฐ์—ด (์ƒ๋žต ๊ฐ€๋Šฅ) - ``` - - **์˜ˆ์ œ : ๋ฐฐ์—ด์˜ ๋ชจ๋“  ์š”์†Œ๊ฐ€ ๊ฐ™์€ ๊ฐ’์ธ์ง€ ํ™•์ธํ•˜๋Š” ์ฝ”๋“œ๋ฅผ ์ž‘์„ฑํ•˜์‹œ์˜ค.** - id:: 68500afb-beda-428b-bab7-e2dceb371325 - **์˜ˆ์‹œ ๋ฐฐ์—ด์€ arr1 = [5,5,5], arr2 = [5,4,5] ๋กœ ์„ ์–ธํ•ด์„œ ํ•  ๊ฒƒ!** #card - - ```javascript - const arr1 = [5, 5, 5]; - const arr2 = [5, 4, 5]; - - arr1.every(v => v===arr1[0]); // true - arr2.every(v => v===arr2[0]); // false - ``` - - - - **arr.slice()** - - **๊ธฐ๋ณธ ์ •์˜** :-> - id:: 68500c5b-9c05-4141-ab0c-3e179450bc03 - **๋ฐฐ์—ด์˜ ์ž…๋ ฅํ•œ ์ธ๋ฑ์Šค๋ถ€ํ„ฐ ๋๊นŒ์ง€์˜ ๋ฐฐ์—ด์„ ๋ฐ˜ํ™˜ํ•˜๋Š” ๋งค์„œ๋“œ** - **์ธ๋ฑ์Šค ๋ฒ”์œ„๋ฅผ ์ดˆ๊ณผํ•ด๋„ ๋นˆ ๋ฐฐ์—ด์„ ๋ฐ˜ํ™˜ํ•˜๊ธฐ ๋•Œ๋ฌธ์— ์—๋Ÿฌ๊ฐ€ ์—†์Œ** - ```javascript - const arr = [1,2,3,4,5]; - arr.slice(3); // [4,5] - arr.slice(5); // [] - ``` - - - - **arr.forEach()** - - **๊ธฐ๋ณธ ์ •์˜** #card - id:: 68500698-1dfa-4aff-9577-359f8fe63c99 - - ```javascript - const arr = [1,2,3,4,5]; - arr.forEach((element, index, array) => { - // element: ํ˜„์žฌ ์š”์†Œ - // index: ํ˜„์žฌ ์ธ๋ฑ์Šค (์ƒ๋žต ๊ฐ€๋Šฅ) - // array: ์›๋ณธ ๋ฐฐ์—ด (์ƒ๋žต ๊ฐ€๋Šฅ) - // ์œ„์˜ ํ˜„์žฌ ์š”์†Œ ๋ฐ ์ธ๋ฑ์Šค, ์›๋ณธ๋ฐฐ์—ด์€ ํŽธํ•œ๊ฑธ๋กœ ๋ฐ”๊ฟ”์„œ ์„ ์–ธํ•ด๋„ ๋จ. - // ์œ„์— ์ง€์ •ํ•œ ๊ฒƒ์„ ๋ณ€์ˆ˜์‚ผ์•„์„œ for๋ฌธ ์•ˆ์˜ ์ฝ”๋“œ๋ฅผ ์ž‘์„ฑํ•˜๋“ฏ ์ฝœ๋ฐฑํ•จ์ˆ˜๋ฅผ ์„ ์–ธ - // ๊ทธ๋Ÿฌ๋ฉด for๋ฌธ ์ฒ˜๋Ÿผ ๊ฐ ์š”์†Œ๋“ค์€ ์ˆœํšŒํ•˜๋ฉฐ ์ฝ”๋“œ๋ฅผ ์‹คํ–‰ํ•จ - }); - ``` - - **๋ฐ˜๋ณต๋ฌธ ์ œ์–ด ํ•จ์ˆ˜์ธ break, continue ์‚ฌ์šฉ๋ฒ•** #card - id:: 685007a1-6eab-4601-b002-6e0724e064d8 - - break๋Š” ์‚ฌ์šฉ ๋ถˆ๊ฐ€(๊ผญ ํ•„์š”ํ•˜๋‹ค๋ฉด ๊ทธ๋ƒฅ for, while, do whlie์„ ์“ธ ๊ฒƒ!) - - continue๋Š” return ์œผ๋กœ ๋Œ€์ฒดํ•ด์„œ ์‚ฌ์šฉํ•จ.(ํ˜„์žฌ ์ธ๋ฑ์Šค์— ๋Œ€ํ•œ ์ˆœํšŒ๋ฅผ ๊ทธ์ฆ‰์‹œ ๋๋‚ด๊ณ  ๋‹ค์Œ์œผ๋กœ ๋„˜์–ด๊ฐ) - - ์˜ˆ์ œ - ```javascript - const arr = [1,2,3,4,5]; - arr.forEach(v => { - if(v===3) return; - console.log(v); - }); - - // ์ถœ๋ ฅ(๊ฐœํ–‰์€ ์ƒ๋žตํ•จ) - // 1 2 4 5 - ``` - - - - **arr.reduce()** - - **๊ธฐ๋ณธ ์ •์˜** #card - id:: 685698f1-be84-4d2a-9440-256b6831989d - - ```javascript - // arr.reduce(<์ฝœ๋ฐฑํ•จ์ˆ˜>,<๋ˆ„์ ๋ณ€์ˆ˜์˜ ์ดˆ๊ธฐ๊ฐ’>) - arr.reduce((accumulator, currentValue, currentIndex, array)=> <ํ•จ์ˆ˜์ฝ”๋“œ>, <๋ˆ„์ ์ž์˜ ์ดˆ๊ธฐ๊ฐ’>) - // accumulator: ์ด์ „ ์š”์†Œ๋ฅผ ์ƒ๋Œ€๋กœ ์ฝœ๋ฐฑ ํ•จ์ˆ˜๋ฅผ ์‹คํ–‰ํ•œ ๊ฒฐ๊ณผ (๋ˆ„์ ์ž) - // currentValue: ํ˜„์žฌ ์š”์†Œ์˜ ๊ฐ’ - // currentIndex: ํ˜„์žฌ ์š”์†Œ์˜ ์ธ๋ฑ์Šค (์ƒ๋žต๊ฐ€๋Šฅ) - // array: reduce() ๋ฉ”์„œ๋“œ๋ฅผ ํ˜ธ์ถœํ•˜๋Š” ๋ฐฐ์—ด (์ƒ๋žต๊ฐ€๋Šฅ) - ``` - - ๋ฐฐ์—ด์˜ ๊ฐ ์š”์†Œ๋ณ„๋กœ ๋ˆ„์ ์ž๋ฅผ ๊ณ„์‚ฐํ•˜๊ณ  ์ตœ์ข…์ ์œผ๋กœ ๋ชจ๋“  ์š”์†Œ๋ฅผ ์ˆœํšŒํ•œ ๋’ค์˜ ๋ˆ„์ ์ž๋ฅผ ๋ฆฌํ„ดํ•จ. - - **์˜ˆ์‹œ (1-10๊นŒ์ง€์˜ ํ•ฉ์„ ๊ตฌํ•˜๊ธฐ)(1-10๊นŒ์ง€ ๋ฐฐ์—ด์„ ํ•œ์ค„๋กœ ์„ ์–ธํ•œ ๋’ค ๊ทธ ๋ฐฐ์—ด์˜ ํ•ฉ์„ ๊ตฌํ•˜๋Š” ๋ฐฉ์‹์œผ๋กœ)** #card - id:: 68569a43-c4bc-4aaf-b07b-aeef8599a43f - - ```javascript - const arr = Array.from({length : 10}, (v,i)=> v=i+1); - const sum = arr.reduce((acc, val) => acc + val, 0); - console.log(sum); // 55 - ``` - - - - **arr.sort()** - - arr์˜ ๋ฐ์ดํ„ฐ๋“ค์„ ์˜ค๋ฆ„์ฐจ์ˆœ์œผ๋กœ ์ •๋ฆฌํ•จ. #card - id:: 68595f48-e964-47fe-9b89-9f0aa4eeed3e - - ๊ธฐ๋ณธ์ ์œผ๋กœ๋Š” ๋ฐ์ดํ„ฐ๋“ค์„ ๋ฌธ์ž์—ด๋กœ ๋ณด๊ณ  ์ •๋ ฌํ•˜๊ธฐ ๋•Œ๋ฌธ์— ์ˆซ์ž๊ฐ€ ์ œ๋Œ€๋กœ ์ •๋ ฌ๋˜์ง€ ์•Š๋Š” ๊ฒฝ์šฐ๊ฐ€ ์žˆ์Œ. - - ๋งค์„œ๋“œ ๊ด„ํ˜ธ ์•ˆ์— ์ฝœ๋ฐฑํ•จ์ˆ˜๋ฅผ ๋„ฃ์–ด์„œ ์ˆซ์ž๋“ค์„ ์ •ํ™•ํ•˜๊ฒŒ ์˜ค๋ฆ„์ฐจ์ˆœ ํ˜น์€ ๋‚ด๋ฆผ์ฐจ์ˆœ์œผ๋กœ ์ •๋ ฌํ•  ์ˆ˜ ์žˆ์Œ. - - ์˜ค๋ฆ„์ฐจ์ˆœ #card - id:: 68595fed-e1f0-4fb3-8c27-6650027c0749 - - ```javascript - let arr = [10,5,7,2]; - arr.sort((a,b)=>a-b); - console.log(arr) // 2,5,7,10 - ``` - - ๋‚ด๋ฆผ์ฐจ์ˆœ #card - id:: 6859607c-2839-490a-9f49-8ba86607905c - - ```javascript - let arr = [10,5,7,2]; - arr.sort((a,b)=>b-a); - console.log(arr) // 10,7,5,2 - ``` - - **python** - - **arr.count(value)** #card - id:: 6857c84c-711b-4865-ba82-92c2d81c0e0b - - ๋ฆฌ์ŠคํŠธ ํ˜น์€ ๋ฌธ์ž์—ด์—์„œ ํŠน์ • ๊ฐ’์˜ ๊ฐœ์ˆ˜๋ฅผ ๋ฆฌํ„ดํ•˜๋Š” ๋งค์„œ๋“œ - - ```python - string = "aaabbcccc" - print(string.count('a')) # 3 - print(string.count('b')) # 2 - print(string.count('c')) # 4 - - arr = [1,2,2,3,3,3,4,4,4,4] - print(arr.count(1)) # 1 - print(arr.count(2)) # 2 - print(arr.count(3)) # 3 - print(arr.count(4)) # 4 - ``` - - **arr.sort()** #card #depth-1 - id:: 685960df-7858-4413-b448-1b34facec439 - - ๋ฆฌ์ŠคํŠธ๋ฅผ ์ •๋ ฌํ•˜๋Š” ๋งค์„œ๋“œ. - - ๋ฆฌ์ŠคํŠธ๋ฅผ ์ •๋ ฌํ•ด์„œ ๊ธฐ์กด ๋ฆฌ์ŠคํŠธ๋ฅผ ์ •๋ ฌ๋œ ํ˜•ํƒœ๋กœ ๋ฐ”๊ฟˆ. - - arr.sort(reverse=True) ์ด๋ ‡๊ฒŒ ํ•˜๋ฉด ๋‚ด๋ฆผ์ฐจ์ˆœ์œผ๋กœ ์ •๋ ฌ๋จ. - - ์˜ˆ์ œ์ฝ”๋“œ #card - id:: 685961bd-0be6-49ff-9a07-f5b2eb371030 - - ```python - arr = [5,8,2,4,9] - arr.sort() # 2 4 5 8 9 - arr.sort(reverse=True) # 9 8 5 4 2 - ``` - - **sorted(arr)** #card #depth-1 - id:: 6859617a-f536-4f57-9cfd-6e4291369c1a - - ์ž…๋ ฅํ•œ ๋ฆฌ์ŠคํŠธ๋ฅผ ์ •๋ ฌํ•ด์„œ ์ƒˆ๋กœ์šด ๋ฆฌ์ŠคํŠธ๋ฅผ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜ - - ๊ธฐ๋ณธ์ ์œผ๋กœ๋Š” ์˜ค๋ฆ„์ฐจ์ˆœ์ •๋ ฌ์ด๊ณ , sorted(arr, reverse=True) ๋กœ ํ•˜๋ฉด ๋‚ด๋ฆผ์ฐจ์ˆœ์ž„. - - ์˜ˆ์ œ์ฝ”๋“œ #card - id:: 68596251-f733-4854-902e-faf055a64330 - - ```python - arr = [5,8,2,4,9] - arr1 = sorted(arr) - arr2 = sorted(arr, reverse=True) - print(arr1) # 2 4 5 8 9 - print(arr2) # 9 8 5 4 2 - ``` - - -- -- ## **์ง„์ˆ˜๋ณ€ํ™˜ ์•Œ๊ณ ๋ฆฌ์ฆ˜** - - **B์ง„์ˆ˜ ์ˆซ์ž N์„ 10์ง„์ˆ˜๋กœ ๋ฐ”๊พธ๋Š” ๋ฒ•(๋ˆ„์ ๊ณฑ ๋ฐฉ์‹)** #card - id:: 68458948-9821-42c7-bb19-85d7c7ad4b8d - - N์˜ ์™ผ์ชฝ๋ถ€ํ„ฐ ํ•œ ์ž๋ฆฌ์”ฉ ๋ˆ„์ ํ•ด์„œ ๊ณฑํ•˜๊ณ  ๋”ํ•˜๋Š” ๋ฐฉ์‹ - - ์•Œ๊ณ ๋ฆฌ์ฆ˜ - - ์ตœ์ข…๊ฒฐ๊ณผ res๋ฅผ 0์œผ๋กœ ์ดˆ๊ธฐํ™” - - ๋ฐ˜๋ณต๋ฌธ์„ ํ†ตํ•ด N์˜ ์™ผ์ชฝ์ˆซ์ž๋ถ€ํ„ฐ ํ•˜๋‚˜์”ฉ ์ˆœํšŒํ•จ. - - ์ˆœํšŒํ•˜๋ฉด์„œ ์ฝ์€ ๊ฐ’์„ 10์ง„์ˆ˜๋กœ ๋ฐ”๊พธ๊ณ (A=10, B=11...) ๊ทธ ๊ฐ’์€ val์— ์ €์žฅ. - - res = res*B + val - - ๋ฐ˜๋ณต๋ฌธ์„ ๋ชจ๋‘ ๋Œ๊ณ  ๋‚˜๋ฉด ์ตœ์ข…์ ์œผ๋กœ res์— ๋ณ€ํ™˜๊ฐ’์ด ๋“ค์–ด๊ฐ€์žˆ์Œ. - - **10์ง„์ˆ˜ ์ˆซ์ž N์„ B์ง„์ˆ˜๋กœ ๋ฐ”๊พธ๋Š” ๋ฒ•(๋‚˜๋จธ์ง€ ๊ณ„์‚ฐ๋ฒ•)** #card - id:: 68458b0d-5584-48bf-8bb4-aad6449b0193 - - N์„ B๋กœ ๊ณ„์† ๋‚˜๋ˆ„๋ฉด์„œ ๊ทธ๋•Œ๋งˆ๋‹ค ๋‚˜๋จธ์ง€๊ฐ’์„ ํ†ตํ•ด ๋ณ€ํ™˜ํ•˜๋Š” ๋ฐฉ์‹ - - ์•Œ๊ณ ๋ฆฌ์ฆ˜ - - ์ตœ์ข… ๊ฒฐ๊ณผ ๋ฌธ์ž์—ด res๋ฅผ ์„ ์–ธ. - - N์ด 0์ด ๋  ๋•Œ๊นŒ์ง€ ๋ฐ˜๋ณต๋ฌธ์„ ์ˆœํšŒํ•จ. - - val์— N์„ B๋กœ ๋‚˜๋ˆˆ ๋‚˜๋จธ์ง€ ๊ฐ’์„ ์ €์žฅ. - - val๊ฐ’์„ ์ง„๋ฒ•์— ๋งž๊ฒŒ ๋ณ€ํ™˜ํ•ด์„œ res์— ๋„ฃ์Œ.(์•ž์—์„œ ๋ถ€ํ„ฐ ๋„ฃ๋Š”๋‹ค) - - N์„ B๋กœ ๋‚˜๋ˆˆ ๋ชซ์œผ๋กœ N์„ ์žฌ์„ ์–ธ(N=N//B) - - ์œ„์˜ ๊ณผ์ •์„ ๋ฐ˜๋ณตํ•œ ๋’ค ๋ฐ˜๋ณต๋ฌธ์„ ๋น ์ ธ๋‚˜์˜ค๋ฉด res์—๋Š” ์ตœ์ข… ๋ณ€ํ™˜๊ฒฐ๊ณผ๊ฐ€ ์—ญ์ˆœ์œผ๋กœ ๋“ค์–ด๊ฐ€์žˆ์Œ. -- -- ## **์†Œ์ˆ˜์  ์˜ฌ๋ฆผ ์—ฐ์‚ฐ** - - **ceilํ•จ์ˆ˜๋ฅผ ์‚ฌ์šฉํ•˜์ง€ ์•Š๋Š” ๋ฐฉ๋ฒ•** #card - id:: 68494b21-76da-4013-a61a-8c8cd812e253 +- ## **Python** + - ### **์ด์ฐจ์› ๋ฐฐ์—ด(n*m) ์ƒ์„ฑ** #card + id:: 6867f994-13d0-4937-90e9-d8aec7be5d67 - ```python - ceil(x/y) = (x+y-1)//y + arr = [[0]*m for _ in range(n)] ``` -- -- ## **์ตœ์†Œ๊ณต๋ฐฐ์ˆ˜/์ตœ๋Œ€๊ณต์•ฝ์ˆ˜ ๊ตฌํ•˜๊ธฐ (์œ ํด๋ฆฌ๋“œ ํ˜ธ์ œ๋ฒ•)** - - **์ตœ๋Œ€๊ณต์•ฝ์ˆ˜(GCD) ๊ตฌํ•˜๊ธฐ** #card #depth-1 - id:: 685d3d73-9ff0-4ec5-88b0-913cc9d52da5 - - ๋‘ ์ˆ˜ a,b๊ฐ€ ์žˆ์„ ๋•Œ, a๋ฅผ b๋กœ ๋‚˜๋ˆˆ ๋‚˜๋จธ์ง€๋ฅผ r์ด๋ผ ํ•˜๋ฉด a์™€ b์˜ ์ตœ๋Œ€๊ณต์•ฝ์ˆ˜๋Š” b์™€ r์˜ ์ตœ๋Œ€๊ณต์•ฝ์ˆ˜์™€ ๊ฐ™๋‹ค. - - ์ฆ‰ ์œ„์˜ ๊ณผ์ •์„ ๊ณ„์† ๋ฐ˜๋ณตํ•ด์„œ ๋‚˜๋จธ์ง€๊ฐ€ 0์ด ๋  ๋•Œ๊นŒ์ง€ ๋ฐ˜๋ณตํ•˜๋ฉด 0์ด๋˜๊ธฐ ์ง์ „์˜ ์ˆ˜๊ฐ€ ์ตœ๋Œ€ ๊ณต์•ฝ์ˆ˜๊ฐ€ ๋œ๋‹ค. - - ์ด๊ฒƒ์€ ๋ฐ˜๋ณต๋ฌธ์œผ๋กœ, ๋˜๋Š” ์žฌ๊ท€ํ•จ์ˆ˜๋กœ ๊ตฌํ•  ์ˆ˜ ์žˆ๋‹ค. - - ์˜ˆ์ œ์ฝ”๋“œ(ํŒŒ์ด์ฌ ๊ธฐ์ค€) - - ์žฌ๊ท€ํ•จ์ˆ˜๋กœ ๊ตฌํ˜„ #card - id:: 685d3e0d-40b4-4dd8-a43e-75ee4044f0a6 - - ```python - def GCD(a,b) : - x = max(a,b) - y = min(a,b) - if x%y == 0 : - return y - else : - return GCD(y, x%y) - - a = 18 - b = 24 - print(GCD(a,b)) # 6 - ``` - - ๋ฐ˜๋ณต๋ฌธ์œผ๋กœ ๊ตฌํ˜„ #card - id:: 685d3fbd-eaa7-438f-b0dc-ab5bfbe9acac - - ```python - a = 18 - b = 24 - - while b != 0: - r = a % b - a = b - b = r - - print(a) # 6 - - ``` - - **์ตœ์†Œ๊ณต๋ฐฐ์ˆ˜(LCM) ๊ตฌํ•˜๊ธฐ** - - ๋‘ ์ˆ˜ a,b์™€ ๊ทธ ์ˆ˜์˜ ์ตœ๋Œ€๊ณต์•ฝ์ˆ˜(GCD)๋ฅผ ์•Œ๋ฉด a,b์˜ ์ตœ์†Œ๊ณต๋ฐฐ์ˆ˜๋Š” ๋‹ค์Œ๊ณผ ๊ฐ™๋‹ค. #card - id:: 685d41ca-1832-434c-a919-0f67a2a37ec0 - - LCM = (a*b) / GCD(a,b) -- -- ## **ํŒŒ์ด์ฌ, ์ž๋ฐ”์Šคํฌ๋ฆฝํŠธ ๋ฐ˜๋ณต๋ฌธ ์ˆœํšŒ ๋ฐ ๊ฐ์ฒด/๋”•์…”๋„ˆ๋ฆฌ ์ˆœํšŒ** - - ### **โ–บ ์ผ๋ฐ˜์ ์ธ ๋ฐ˜๋ณต๊ฐ€๋Šฅ ๊ฐ์ฒด๋ฅผ ํ™œ์šฉํ•œ ๋ฐ˜๋ณต๋ฌธ ์ˆœํšŒ(๊ธฐ๋ณธ ์ˆœํšŒ)** - - **โ— pythron** #card - id:: 684e9cfd-e828-43ac-9f6c-76492bdcf94a - - ```python - arr = [1,2,3,4,5] - - for i in arr : - print(i) - - # ์ถœ๋ ฅ - # 1 2 3 4 5 - ``` - - **โ— javascript** #card - id:: 684e9d25-ddf8-4f7c-b781-21bb247497f8 - - ```javascript - const arr = [1,2,3,4,5]; - - for(let i of arr) { - console.log(i); - } - - // ์ถœ๋ ฅ - // 1 2 3 4 5 - ``` - - - - ### **โ–บ ์ž๋ฐ”์Šคํฌ๋ฆฝํŠธ์˜ ๊ฐ์ฒด(Object) ๋Š” ํŒŒ์ด์ฌ์˜ ๋”•์…”๋„ˆ๋ฆฌ(Dictionary)** - - **ํ‚ค(key)์™€ ๊ฐ’(value)์„ ๊ฐ€์ง€๋Š” ๋ฐ์ดํ„ฐ์˜ ์ง‘ํ•ฉ(๊ฐ๊ฐ์˜ ์–ธ์–ด์—์„œ ์„œ๋กœ ๋™์ผํ•˜๋‹ค๊ณ  ์ƒ๊ฐํ•ด๋„ ๋ฌด๋ฐฉํ•จ)** - - **โ—Ž ์„ ์–ธ ๋ฐ ์ ‘๊ทผ๋ฐฉ๋ฒ•** - - **โ— pythron** #card - id:: 684e9fb3-3cf0-4fa0-8539-e53bfe7fbcc1 - - ```python - # ๋นˆ๋ฐ์ดํ„ฐ ์ดˆ๊ธฐํ™” ๋ฐฉ๋ฒ• - dic = {} # dict() - - # ์ง์ ‘ ์„ ์–ธ ๋ฐฉ๋ฒ• - dic = { - "name": "Yechan", - "age" : 30 - } - - # ์ถœ๋ ฅ - print(dic["name"]) - print(dic["age"]) - # Yechan - # 30 - ``` - - **โ— javascript** #card - id:: 684ea0a5-0720-4a7b-a3b0-6fd81541ec05 - - ```javascript - // ๋นˆ๋ฐ์ดํ„ฐ ์ดˆ๊ธฐํ™” ๋ฐฉ๋ฒ• - let obj = {}; - - // ์ง์ ‘ ์„ ์–ธ ๋ฐฉ๋ฒ• - let obj = { - "name": "Yechan", - "age" : 30 - }; - - // ์ถœ๋ ฅ - console.log(obj.name); - console.log(obj["age"]); - // Yechan - // 30 - // ๋‘ ๋ฐฉ๋ฒ• ๋ชจ๋‘ ์‚ฌ์šฉ ๊ฐ€๋Šฅ - ``` - - **โ—Ž ํ‚ค ๋ฐ ๊ฐ’ ์ˆœํšŒ(๋ฐ˜๋ณต๋ฌธ ์‚ฌ์šฉ, ์ˆœ์„œ๋Š” ๋ณด์žฅ๋˜์ง€ ์•Š์Œ)** - - **โ— pythron** #card - id:: c506e90a-c84b-4498-ba5f-5028f5a874f6 - - ```python - dic = { - "name": "Yechan", - "age" : 30 - } - - # key ์ˆœํšŒ - for key in dic : - print(dic[key]) - # Yechan - # 30 - - # key, value ์ˆœํšŒ - for key, value in dic.items() : - print(key, value) - # name Yechan - # age 30 - ``` - - **โ— javascript** #card - id:: f380d0d7-7826-4714-bb8c-c78cc601ca50 - - ```javascript - let obj = { - "name": "Yechan", - "age" : 30 - }; - - // key ์ˆœํšŒ - for(let key in obj){ - console.log(obj[key]); - } - // Yechan - // 30 - - // key, value ์ˆœํšŒ - for [key, value] of Object.entries(obj) { - console.log(key, value); - } - // name Yechan - // age 30 - - for key of Object.keys(obj) { - console.log(key, obj[key]); - } - // name Yechan - // age 30 - ``` - - - - ### **โ–บ ํŒŒ์ด์ฌ์—์„œ ๋ฐ˜๋ณต๊ฐ€๋Šฅํ•œ ๋ฐ์ดํ„ฐ์…‹์˜ ๊ฐ’๊ณผ ์ธ๋ฑ์Šค๋ฅผ ๋ถˆ๋Ÿฌ์™€์„œ ์ˆœํšŒํ•˜๊ธฐ** - - **enumerate()** #card #depth-1 - id:: 6857c511-ce76-4075-ba45-a38956deb7df - - ๋ฐ˜๋ณต๊ฐ€๋Šฅํ•œ ๋ฐ์ดํ„ฐ์…‹์˜ ๊ฐ’๊ณผ ์ธ๋ฑ์Šค๋ฅผ ํŠœํ”Œํ˜•ํƒœ๋กœ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜ #card - id:: 6857c541-93f0-441f-8ff1-ca3cf8a3b186 - - ```python - arr = ["apple", "banana", "cat"] - for i in enumerate(arr) : - print(i) - # ์ถœ๋ ฅ - # (0, apple) - # (1, banana) - # (2, cat) - ``` - - ๋ฐ˜๋ณต๋ฌธ์—์„œ ์ธ๋ฑ์Šค์™€ ๊ฐ’์„ ๋™์‹œ์— ์ˆœํšŒํ•  ์ˆ˜ ์žˆ์Œ. #card - id:: 6857c6b6-3201-47a1-a090-c0ebe75d5e4c - - ```python - arr = ["apple", "banana", "cat"] - for index, value in enumerate(arr) : - print(index, value) - # ์ถœ๋ ฅ - # 0 apple - # 1 banana - # 2 cat - ``` - - ์‹œ์ž‘ ์ธ๋ฑ์Šค๋ฅผ ๋ฐ”๊ฟ€ ์ˆ˜๋„ ์žˆ์Œ. #card - id:: 6857c623-b8e4-4325-a8c2-27a9446118bd - - ```python - arr = ["apple", "banana", "cat"] - for index, value in enumerate(arr, start=1) : - print(index, value) - # ์ถœ๋ ฅ - # 1 apple - # 2 banana - # 3 cat - ``` - - -- -- ## **C์–ธ์–ด ๋ณ€์ˆ˜ ํƒ€์ž…๋ณ„ ๋ฉ”๋ชจ๋ฆฌ ํ• ๋‹นํฌ๊ธฐ ์ •๋ฆฌ** - - ### **๋นˆ์นธ ์ฑ„์›Œ๋ณด๊ธฐ** - id:: 684ea7e1-e59d-47a5-971f-2114a17fdda7 - - ![image.png](../assets/image_1749986661502_0.png) #card - id:: 684eae27-cd8a-4043-b999-d51b71757544 - - ![image.png](../assets/image_1749986614051_0.png) - id:: 684ea656-cac9-45ba-8dc4-5ade273c8777 -- -- ## **๋น„ํŠธ์—ฐ์‚ฐ ์ •๋ฆฌ** - - ### **XOR(๋ฐฐํƒ€์  ๋…ผ๋ฆฌํ•ฉ)** - - ๊ธฐํ˜ธ : :-> ^ - id:: 684eaf61-54bb-4f69-af87-f75f280bd119 - - ์—ฐ์‚ฐ๊ฐ’ : :-> (0,0)->0, (0,1)->1, (1,0)->1, (1,1)->0 [๊ฐ™์œผ๋ฉด 0, ๋‹ค๋ฅด๋ฉด 1] - id:: 684eafb2-7091-4d69-8c3f-0540d687b782 - - ํ•ต์‹ฌ์„ฑ์งˆ #card - id:: 684eaff6-5a2b-4cdd-ba5d-cba163b087fa - - ๊ฐ™์€ ๊ฐ’๋ผ๋ฆฌ XORํ•˜๋ฉด 0์ด ๋œ๋‹ค: `a ^ a = 0` - - 0๊ณผ XORํ•˜๋ฉด ์ž๊ธฐ ์ž์‹ ์ด ๋œ๋‹ค: `a ^ 0 = a` - - ๊ตํ™˜๋ฒ•์น™, ๊ฒฐํ•ฉ๋ฒ•์น™์ด ์„ฑ๋ฆฝํ•œ๋‹ค: `a ^ b = b ^ a`, `(a ^ b) ^ c = a ^ (b ^ c)` - - ํ™œ์šฉ #card #depth-1 - id:: 684eb038-f987-419b-b531-2b7a868c0842 - - ์ค‘๋ณต๋˜๋Š” ์—ฌ๋Ÿฌ ์ˆ˜๋“ค ์ค‘์— ๋‹จ ํ•˜๋‚˜ ๋‹ค๋ฅธ ์ˆ˜๋ฅผ ์ฐพ๋Š” ๋ฐฉ๋ฒ•์œผ๋กœ ํ™œ์šฉ #card - id:: 684eb045-4df8-4943-bdfb-65f983f2704e - - ๋ชจ๋“  ์ˆ˜๋ฅผ ํ•˜๋‚˜ํ•˜๋‚˜ xorํ•˜๋ฉด ๊ฒฐ๊ตญ ์ตœ์ข…์ ์œผ๋กœ ๋‚˜์˜ค๋Š” ๊ฒฐ๊ณผ๋Š” ๋‹ค๋ฅธ ํ•˜๋‚˜๊ฐ€ ๋‚˜์˜ด. - - ```C - int arr[] = {1, 2, 3, 2, 1}; - int res = 0; - for(int i=0; i<5; i++) res ^= arr[i]; - // res == 3 (์ง์ด ์—†๋Š” ๊ฐ’) - ``` - - ์ค‘๋ณต๋˜๋Š” ์ˆ˜๊ฐ€ ํ™€์ˆ˜๊ฐœ๋กœ ์ง์ง€์–ด์ ธ ์žˆ์œผ๋ฉด ์‚ฌ์šฉํ•  ์ˆ˜ ์—†์Œ - - ๋‹จ ๋‹จ ํ•˜๋‚˜์˜ ์ˆ˜๋ฅผ ์ œ์™ธํ•œ ๋ชจ๋“  ์ˆ˜๊ฐ€ ๊ฐ™์€ ์ˆซ์ž๋ผ๋ฉด ์‚ฌ์šฉ ๊ฐ€๋Šฅ - - ์ž„์‹œ๋ณ€์ˆ˜ ์—†์ด ๋‘ ๋ณ€์ˆ˜์˜ ๊ฐ’์„ swap #card - id:: 684eb1a1-f13d-45c3-b03b-da9372da5e7c - - XOR ์—ฐ์‚ฐ์˜ ์„ฑ์งˆ์„ ์ž˜ ์‘์šฉํ•˜๋ฉด ์•„๋ž˜์˜ ์ฝ”๋“œ์ฒ˜๋Ÿผ ๋‘ ๋ณ€์ˆ˜๋ฅผ ๊ตํ™˜ํ•  ์ˆ˜ ์žˆ์Œ. - - ```C - int a = 3; - int b = 5; - - a = a ^ b; - b = a ^ b; - a = a ^ b; - // ์ด์ œ a=5, b=3 (๊ฐ’์ด ์„œ๋กœ ๋ฐ”๋€œ) - ``` -- -- ## **์ž๋ฐ”์Šคํฌ๋ฆฝํŠธ ํŠน์ง•๊ด€๋ จ ๋‚ด์šฉ** - - **ํ™”์‚ดํ‘œ ํ•จ์ˆ˜** - - ์ •์˜ #card - id:: 685d3bc9-b9df-4cc9-be77-d6f26ee73924 - - ํ•จ์ˆ˜๋ฅผ funcion์œผ๋กœ ๋”ฐ๋กœ ์„ ์–ธํ•ด์„œ ์‚ฌ์šฉํ•˜๋Š” ๊ฒƒ์ด ์•„๋‹Œ ํ•œ์ค„, ํ˜น์€ ์—ฌ๋Ÿฌ์ค„๋กœ ๊ฐ„๊ฒฐํ•˜๊ฒŒ ํ‘œํ˜„ํ•˜๋Š” ํ‘œํ˜„์‹์˜ ํ•œ ํ˜•ํƒœ. - - ```javascript - // ๊ธฐ์กด ํ•จ์ˆ˜ ์„ ์–ธ ๋ฐฉ์‹ - function sum(a, b) { - return a+b; - } - - // ํ™”์‚ดํ‘œ ํ•จ์ˆ˜ - const sum = (a,b) => a+b; - ``` - - ์‚ฌ์šฉ๋ฐฉ๋ฒ• #card - id:: 685d3bec-8254-43a8-9d7a-fada78a05b6a - - ๋ณ€์ˆ˜ํƒ€์ž… ๋ฐ ํ•จ์ˆ˜๋ช…์„ ์“ฐ๊ณ  ๊ทธ ๋’ค์— =์„ ๋ถ™์ธ ๋’ค ๋ณ€์ˆ˜๋“ค์„ ๊ด„ํ˜ธ๋กœ ์ง€์ •ํ•œ ๋’ค => ๊ธฐํ˜ธ๋กœ ์—ฐ๊ฒฐ. - - ์ด ํ›„ ํ™”์‚ดํ‘œ ๋’ค์— ํ•จ์ˆ˜๋ฅผ ์ ์œผ๋ฉด ๋จ. - - ์ด ๋’ค์˜ ํ•จ์ˆ˜๊ฐ€ ํ•œ์ค„์ด๋ฉด return์„ ์“ฐ์ง€ ์•Š์•„๋„ ์•Œ์•„์„œ ๋ฐ˜ํ™˜ํ•จ. - - ์—ฌ๋Ÿฌ์ค„ ์ผ ๊ฒฝ์šฐ์—๋Š” ์ค‘๊ด„ํ˜ธ๋ฅผ ์“ฐ๊ณ , ์ด๋•Œ๋Š” ๊ผญ return์„ ์จ์ค˜์•ผ ํ•จ. - - ```javascript - // ํ•œ ์ค„, ์•”์‹œ์  ๋ฐ˜ํ™˜ - const sum = (a, b) => a + b; - - // ์—ฌ๋Ÿฌ ์ค„, ๋ช…์‹œ์  ๋ฐ˜ํ™˜ ํ•„์š” - const multiply = (a, b) => { - const result = a * b; - return result; - }; - ``` - - ์˜ˆ์‹œ์ฝ”๋“œ - - ํ•œ ์ค„๋กœ ํ‘œํ˜„, ์ž…๋ ฅ๊ฐ’์˜ 2๋ฐฐ๋ฅผ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜ ์„ ์–ธ #card - id:: 685d3c87-2b8e-410e-87f6-9166619ab636 - - ```javascript - const double = x => x*2; - - console.log(double(10)); // 20 - ``` - - ์—ฌ๋Ÿฌ์ค„ ํ‘œํ˜„, ๋‘ ์ˆ˜๋ฅผ ์ž…๋ ฅ๋ฐ›์•„์„œ ๊ทธ ๋‘ ์ˆ˜๋ฅผ ๊ณฑํ•œ ๊ฐ’์„ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜ ์„ ์–ธ #card - id:: 685d3cd9-6924-4800-a57d-61f5d37193db - - ```javascript - const multiply = (a,b) => { - const result = a*b; - return result; - }; - - console.log(multiply(10,5)); // 50 - ``` \ No newline at end of file +- ## **C** +- ## **Java** +- ## **ํ”„๋กœ๊ทธ๋ž˜๋ฐ ๊ด€๋ จ ์ด๋ก  ์ •๋ฆฌ** \ No newline at end of file diff --git a/pages/๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ_์ด์ „.md b/pages/๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ_์ด์ „.md new file mode 100644 index 0000000..650fc1e --- /dev/null +++ b/pages/๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ_์ด์ „.md @@ -0,0 +1,502 @@ +deck:: Logseq/coding tip + +- ## **๊ฐ ์–ธ์–ด๋ณ„ 2์ฐจ์› ๋ฐฐ์—ด(n*m) ์ƒ์„ฑ** + - **Javascript** + - id:: 684578c3-84af-4595-af7a-dc46f58bd99b + 1. ํ•œ์ค„๋กœ ์„ ์–ธํ•˜๊ธฐ(2๊ฐ€์ง€ ๋ฐฉ๋ฒ•) + - ```javascript + const arr = Array.from({ length: n }, () => new Array(m).fill(0)); + + const arr = new Array(n).fill().map(() => new Array(m).fill(0)); + ``` + - id:: 68457909-49bf-4cab-b5fc-c61081c0aa0c + 2. ๋ฐ˜๋ณต๋ฌธ์œผ๋กœ ์ค‘์ฒฉํ•ด์„œ ์ƒ์„ฑํ•˜๊ธฐ + - ```javascript + let arr = []; + for (let i = 0; i < n; i++) { + arr[i] = []; + for (let j = 0; j < m; j++) { + arr[i][j] = 0; + } + } + ``` + - id:: 684577c9-7ecc-4ac9-a959-40f1d7593b1b + 3. ๊ฐ’์ด ์ •ํ•ด์ ธ์žˆ๋Š” ๊ฒฝ์šฐ + - ```javascript + const arr = [ + [1, 2, 3], + [4, 5, 6], + [7, 8, 9] + ]; + ``` + - **python** + - id:: 82ac6ae7-4155-407c-ac0a-78f00ed46c6a + 1. ํ•œ์ค„๋กœ ์„ ์–ธํ•˜๊ธฐ + - ```python + arr = [[0]*m for _ in range(n)] + ``` +- +- ## **๋ฐฐ์—ด๊ด€๋ จ ํŒ ๋ชจ์Œ** + - **Javascript** + - **arr.every()** + - **๊ธฐ๋ณธ ์ •์˜** + id:: 68500a89-08d4-48b2-aa6b-c465041f065b + **๋ฐฐ์—ด์˜ ๋ชจ๋“  ์š”์†Œ๊ฐ€ ์กฐ๊ฑด์‹์„ ๋งŒ์กฑํ•˜๋Š”์ง€ ํ™•์ธํ•ด์„œ T/F๋ฅผ ๋ฐ˜ํ™˜ํ•˜๋Š” ๋งค์„œ๋“œ** + ```javascript + const arr = [1,2,3,4,5]; + arr.every((element, index, array) => {์กฐ๊ฑด์‹}); + // element: ํ˜„์žฌ ์š”์†Œ + // index: ํ˜„์žฌ ์ธ๋ฑ์Šค (์ƒ๋žต ๊ฐ€๋Šฅ) + // array: ์›๋ณธ ๋ฐฐ์—ด (์ƒ๋žต ๊ฐ€๋Šฅ) + ``` + - **์˜ˆ์ œ : ๋ฐฐ์—ด์˜ ๋ชจ๋“  ์š”์†Œ๊ฐ€ ๊ฐ™์€ ๊ฐ’์ธ์ง€ ํ™•์ธํ•˜๋Š” ์ฝ”๋“œ๋ฅผ ์ž‘์„ฑํ•˜์‹œ์˜ค.** + id:: 68500afb-beda-428b-bab7-e2dceb371325 + collapsed:: true + **์˜ˆ์‹œ ๋ฐฐ์—ด์€ arr1 = [5,5,5], arr2 = [5,4,5] ๋กœ ์„ ์–ธํ•ด์„œ ํ•  ๊ฒƒ!** + - ```javascript + const arr1 = [5, 5, 5]; + const arr2 = [5, 4, 5]; + + arr1.every(v => v===arr1[0]); // true + arr2.every(v => v===arr2[0]); // false + ``` + - + - **arr.slice()** + - **๊ธฐ๋ณธ ์ •์˜** + id:: 68500c5b-9c05-4141-ab0c-3e179450bc03 + **๋ฐฐ์—ด์˜ ์ž…๋ ฅํ•œ ์ธ๋ฑ์Šค๋ถ€ํ„ฐ ๋๊นŒ์ง€์˜ ๋ฐฐ์—ด์„ ๋ฐ˜ํ™˜ํ•˜๋Š” ๋งค์„œ๋“œ** + **์ธ๋ฑ์Šค ๋ฒ”์œ„๋ฅผ ์ดˆ๊ณผํ•ด๋„ ๋นˆ ๋ฐฐ์—ด์„ ๋ฐ˜ํ™˜ํ•˜๊ธฐ ๋•Œ๋ฌธ์— ์—๋Ÿฌ๊ฐ€ ์—†์Œ** + ```javascript + const arr = [1,2,3,4,5]; + arr.slice(3); // [4,5] + arr.slice(5); // [] + ``` + - + - **arr.forEach()** + - **๊ธฐ๋ณธ ์ •์˜** + id:: 68500698-1dfa-4aff-9577-359f8fe63c99 + - ```javascript + const arr = [1,2,3,4,5]; + arr.forEach((element, index, array) => { + // element: ํ˜„์žฌ ์š”์†Œ + // index: ํ˜„์žฌ ์ธ๋ฑ์Šค (์ƒ๋žต ๊ฐ€๋Šฅ) + // array: ์›๋ณธ ๋ฐฐ์—ด (์ƒ๋žต ๊ฐ€๋Šฅ) + // ์œ„์˜ ํ˜„์žฌ ์š”์†Œ ๋ฐ ์ธ๋ฑ์Šค, ์›๋ณธ๋ฐฐ์—ด์€ ํŽธํ•œ๊ฑธ๋กœ ๋ฐ”๊ฟ”์„œ ์„ ์–ธํ•ด๋„ ๋จ. + // ์œ„์— ์ง€์ •ํ•œ ๊ฒƒ์„ ๋ณ€์ˆ˜์‚ผ์•„์„œ for๋ฌธ ์•ˆ์˜ ์ฝ”๋“œ๋ฅผ ์ž‘์„ฑํ•˜๋“ฏ ์ฝœ๋ฐฑํ•จ์ˆ˜๋ฅผ ์„ ์–ธ + // ๊ทธ๋Ÿฌ๋ฉด for๋ฌธ ์ฒ˜๋Ÿผ ๊ฐ ์š”์†Œ๋“ค์€ ์ˆœํšŒํ•˜๋ฉฐ ์ฝ”๋“œ๋ฅผ ์‹คํ–‰ํ•จ + }); + ``` + - **๋ฐ˜๋ณต๋ฌธ ์ œ์–ด ํ•จ์ˆ˜์ธ break, continue ์‚ฌ์šฉ๋ฒ•** + id:: 685007a1-6eab-4601-b002-6e0724e064d8 + - break๋Š” ์‚ฌ์šฉ ๋ถˆ๊ฐ€(๊ผญ ํ•„์š”ํ•˜๋‹ค๋ฉด ๊ทธ๋ƒฅ for, while, do whlie์„ ์“ธ ๊ฒƒ!) + - continue๋Š” return ์œผ๋กœ ๋Œ€์ฒดํ•ด์„œ ์‚ฌ์šฉํ•จ.(ํ˜„์žฌ ์ธ๋ฑ์Šค์— ๋Œ€ํ•œ ์ˆœํšŒ๋ฅผ ๊ทธ์ฆ‰์‹œ ๋๋‚ด๊ณ  ๋‹ค์Œ์œผ๋กœ ๋„˜์–ด๊ฐ) + - ์˜ˆ์ œ + ```javascript + const arr = [1,2,3,4,5]; + arr.forEach(v => { + if(v===3) return; + console.log(v); + }); + + // ์ถœ๋ ฅ(๊ฐœํ–‰์€ ์ƒ๋žตํ•จ) + // 1 2 4 5 + ``` + - + - **arr.reduce()** + - **๊ธฐ๋ณธ ์ •์˜** + id:: 685698f1-be84-4d2a-9440-256b6831989d + - ```javascript + // arr.reduce(<์ฝœ๋ฐฑํ•จ์ˆ˜>,<๋ˆ„์ ๋ณ€์ˆ˜์˜ ์ดˆ๊ธฐ๊ฐ’>) + arr.reduce((accumulator, currentValue, currentIndex, array)=> <ํ•จ์ˆ˜์ฝ”๋“œ>, <๋ˆ„์ ์ž์˜ ์ดˆ๊ธฐ๊ฐ’>) + // accumulator: ์ด์ „ ์š”์†Œ๋ฅผ ์ƒ๋Œ€๋กœ ์ฝœ๋ฐฑ ํ•จ์ˆ˜๋ฅผ ์‹คํ–‰ํ•œ ๊ฒฐ๊ณผ (๋ˆ„์ ์ž) + // currentValue: ํ˜„์žฌ ์š”์†Œ์˜ ๊ฐ’ + // currentIndex: ํ˜„์žฌ ์š”์†Œ์˜ ์ธ๋ฑ์Šค (์ƒ๋žต๊ฐ€๋Šฅ) + // array: reduce() ๋ฉ”์„œ๋“œ๋ฅผ ํ˜ธ์ถœํ•˜๋Š” ๋ฐฐ์—ด (์ƒ๋žต๊ฐ€๋Šฅ) + ``` + - ๋ฐฐ์—ด์˜ ๊ฐ ์š”์†Œ๋ณ„๋กœ ๋ˆ„์ ์ž๋ฅผ ๊ณ„์‚ฐํ•˜๊ณ  ์ตœ์ข…์ ์œผ๋กœ ๋ชจ๋“  ์š”์†Œ๋ฅผ ์ˆœํšŒํ•œ ๋’ค์˜ ๋ˆ„์ ์ž๋ฅผ ๋ฆฌํ„ดํ•จ. + - **์˜ˆ์‹œ (1-10๊นŒ์ง€์˜ ํ•ฉ์„ ๊ตฌํ•˜๊ธฐ)(1-10๊นŒ์ง€ ๋ฐฐ์—ด์„ ํ•œ์ค„๋กœ ์„ ์–ธํ•œ ๋’ค ๊ทธ ๋ฐฐ์—ด์˜ ํ•ฉ์„ ๊ตฌํ•˜๋Š” ๋ฐฉ์‹์œผ๋กœ)** + id:: 68569a43-c4bc-4aaf-b07b-aeef8599a43f + - ```javascript + const arr = Array.from({length : 10}, (v,i)=> v=i+1); + const sum = arr.reduce((acc, val) => acc + val, 0); + console.log(sum); // 55 + ``` + - + - **arr.sort()** + - arr์˜ ๋ฐ์ดํ„ฐ๋“ค์„ ์˜ค๋ฆ„์ฐจ์ˆœ์œผ๋กœ ์ •๋ฆฌํ•จ. + id:: 68595f48-e964-47fe-9b89-9f0aa4eeed3e + - ๊ธฐ๋ณธ์ ์œผ๋กœ๋Š” ๋ฐ์ดํ„ฐ๋“ค์„ ๋ฌธ์ž์—ด๋กœ ๋ณด๊ณ  ์ •๋ ฌํ•˜๊ธฐ ๋•Œ๋ฌธ์— ์ˆซ์ž๊ฐ€ ์ œ๋Œ€๋กœ ์ •๋ ฌ๋˜์ง€ ์•Š๋Š” ๊ฒฝ์šฐ๊ฐ€ ์žˆ์Œ. + - ๋งค์„œ๋“œ ๊ด„ํ˜ธ ์•ˆ์— ์ฝœ๋ฐฑํ•จ์ˆ˜๋ฅผ ๋„ฃ์–ด์„œ ์ˆซ์ž๋“ค์„ ์ •ํ™•ํ•˜๊ฒŒ ์˜ค๋ฆ„์ฐจ์ˆœ ํ˜น์€ ๋‚ด๋ฆผ์ฐจ์ˆœ์œผ๋กœ ์ •๋ ฌํ•  ์ˆ˜ ์žˆ์Œ. + - ์˜ค๋ฆ„์ฐจ์ˆœ + id:: 68595fed-e1f0-4fb3-8c27-6650027c0749 + - ```javascript + let arr = [10,5,7,2]; + arr.sort((a,b)=>a-b); + console.log(arr) // 2,5,7,10 + ``` + - ๋‚ด๋ฆผ์ฐจ์ˆœ + id:: 6859607c-2839-490a-9f49-8ba86607905c + - ```javascript + let arr = [10,5,7,2]; + arr.sort((a,b)=>b-a); + console.log(arr) // 10,7,5,2 + ``` + - **python** + - **arr.count(value)** + id:: 6857c84c-711b-4865-ba82-92c2d81c0e0b + - ๋ฆฌ์ŠคํŠธ ํ˜น์€ ๋ฌธ์ž์—ด์—์„œ ํŠน์ • ๊ฐ’์˜ ๊ฐœ์ˆ˜๋ฅผ ๋ฆฌํ„ดํ•˜๋Š” ๋งค์„œ๋“œ + - ```python + string = "aaabbcccc" + print(string.count('a')) # 3 + print(string.count('b')) # 2 + print(string.count('c')) # 4 + + arr = [1,2,2,3,3,3,4,4,4,4] + print(arr.count(1)) # 1 + print(arr.count(2)) # 2 + print(arr.count(3)) # 3 + print(arr.count(4)) # 4 + ``` + - **arr.sort()**-1 + id:: 685960df-7858-4413-b448-1b34facec439 + - ๋ฆฌ์ŠคํŠธ๋ฅผ ์ •๋ ฌํ•˜๋Š” ๋งค์„œ๋“œ. + - ๋ฆฌ์ŠคํŠธ๋ฅผ ์ •๋ ฌํ•ด์„œ ๊ธฐ์กด ๋ฆฌ์ŠคํŠธ๋ฅผ ์ •๋ ฌ๋œ ํ˜•ํƒœ๋กœ ๋ฐ”๊ฟˆ. + - arr.sort(reverse=True) ์ด๋ ‡๊ฒŒ ํ•˜๋ฉด ๋‚ด๋ฆผ์ฐจ์ˆœ์œผ๋กœ ์ •๋ ฌ๋จ. + - ์˜ˆ์ œ์ฝ”๋“œ + id:: 685961bd-0be6-49ff-9a07-f5b2eb371030 + - ```python + arr = [5,8,2,4,9] + arr.sort() # 2 4 5 8 9 + arr.sort(reverse=True) # 9 8 5 4 2 + ``` + - **sorted(arr)** + id:: 6859617a-f536-4f57-9cfd-6e4291369c1a + - ์ž…๋ ฅํ•œ ๋ฆฌ์ŠคํŠธ๋ฅผ ์ •๋ ฌํ•ด์„œ ์ƒˆ๋กœ์šด ๋ฆฌ์ŠคํŠธ๋ฅผ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜ + - ๊ธฐ๋ณธ์ ์œผ๋กœ๋Š” ์˜ค๋ฆ„์ฐจ์ˆœ์ •๋ ฌ์ด๊ณ , sorted(arr, reverse=True) ๋กœ ํ•˜๋ฉด ๋‚ด๋ฆผ์ฐจ์ˆœ์ž„. + - ์˜ˆ์ œ์ฝ”๋“œ + id:: 68596251-f733-4854-902e-faf055a64330 + - ```python + arr = [5,8,2,4,9] + arr1 = sorted(arr) + arr2 = sorted(arr, reverse=True) + print(arr1) # 2 4 5 8 9 + print(arr2) # 9 8 5 4 2 + ``` + - +- +- ## **์ง„์ˆ˜๋ณ€ํ™˜ ์•Œ๊ณ ๋ฆฌ์ฆ˜** + - **B์ง„์ˆ˜ ์ˆซ์ž N์„ 10์ง„์ˆ˜๋กœ ๋ฐ”๊พธ๋Š” ๋ฒ•(๋ˆ„์ ๊ณฑ ๋ฐฉ์‹)** + id:: 68458948-9821-42c7-bb19-85d7c7ad4b8d + - N์˜ ์™ผ์ชฝ๋ถ€ํ„ฐ ํ•œ ์ž๋ฆฌ์”ฉ ๋ˆ„์ ํ•ด์„œ ๊ณฑํ•˜๊ณ  ๋”ํ•˜๋Š” ๋ฐฉ์‹ + - ์•Œ๊ณ ๋ฆฌ์ฆ˜ + - ์ตœ์ข…๊ฒฐ๊ณผ res๋ฅผ 0์œผ๋กœ ์ดˆ๊ธฐํ™” + - ๋ฐ˜๋ณต๋ฌธ์„ ํ†ตํ•ด N์˜ ์™ผ์ชฝ์ˆซ์ž๋ถ€ํ„ฐ ํ•˜๋‚˜์”ฉ ์ˆœํšŒํ•จ. + - ์ˆœํšŒํ•˜๋ฉด์„œ ์ฝ์€ ๊ฐ’์„ 10์ง„์ˆ˜๋กœ ๋ฐ”๊พธ๊ณ (A=10, B=11...) ๊ทธ ๊ฐ’์€ val์— ์ €์žฅ. + - res = res*B + val + - ๋ฐ˜๋ณต๋ฌธ์„ ๋ชจ๋‘ ๋Œ๊ณ  ๋‚˜๋ฉด ์ตœ์ข…์ ์œผ๋กœ res์— ๋ณ€ํ™˜๊ฐ’์ด ๋“ค์–ด๊ฐ€์žˆ์Œ. + - **10์ง„์ˆ˜ ์ˆซ์ž N์„ B์ง„์ˆ˜๋กœ ๋ฐ”๊พธ๋Š” ๋ฒ•(๋‚˜๋จธ์ง€ ๊ณ„์‚ฐ๋ฒ•)** + id:: 68458b0d-5584-48bf-8bb4-aad6449b0193 + - N์„ B๋กœ ๊ณ„์† ๋‚˜๋ˆ„๋ฉด์„œ ๊ทธ๋•Œ๋งˆ๋‹ค ๋‚˜๋จธ์ง€๊ฐ’์„ ํ†ตํ•ด ๋ณ€ํ™˜ํ•˜๋Š” ๋ฐฉ์‹ + - ์•Œ๊ณ ๋ฆฌ์ฆ˜ + - ์ตœ์ข… ๊ฒฐ๊ณผ ๋ฌธ์ž์—ด res๋ฅผ ์„ ์–ธ. + - N์ด 0์ด ๋  ๋•Œ๊นŒ์ง€ ๋ฐ˜๋ณต๋ฌธ์„ ์ˆœํšŒํ•จ. + - val์— N์„ B๋กœ ๋‚˜๋ˆˆ ๋‚˜๋จธ์ง€ ๊ฐ’์„ ์ €์žฅ. + - val๊ฐ’์„ ์ง„๋ฒ•์— ๋งž๊ฒŒ ๋ณ€ํ™˜ํ•ด์„œ res์— ๋„ฃ์Œ.(์•ž์—์„œ ๋ถ€ํ„ฐ ๋„ฃ๋Š”๋‹ค) + - N์„ B๋กœ ๋‚˜๋ˆˆ ๋ชซ์œผ๋กœ N์„ ์žฌ์„ ์–ธ(N=N//B) + - ์œ„์˜ ๊ณผ์ •์„ ๋ฐ˜๋ณตํ•œ ๋’ค ๋ฐ˜๋ณต๋ฌธ์„ ๋น ์ ธ๋‚˜์˜ค๋ฉด res์—๋Š” ์ตœ์ข… ๋ณ€ํ™˜๊ฒฐ๊ณผ๊ฐ€ ์—ญ์ˆœ์œผ๋กœ ๋“ค์–ด๊ฐ€์žˆ์Œ. +- +- ## **์†Œ์ˆ˜์  ์˜ฌ๋ฆผ ์—ฐ์‚ฐ** + - **ceilํ•จ์ˆ˜๋ฅผ ์‚ฌ์šฉํ•˜์ง€ ์•Š๋Š” ๋ฐฉ๋ฒ•** + id:: 68494b21-76da-4013-a61a-8c8cd812e253 + - ```python + ceil(x/y) = (x+y-1)//y + ``` +- +- ## **์ตœ์†Œ๊ณต๋ฐฐ์ˆ˜/์ตœ๋Œ€๊ณต์•ฝ์ˆ˜ ๊ตฌํ•˜๊ธฐ (์œ ํด๋ฆฌ๋“œ ํ˜ธ์ œ๋ฒ•)** + - **์ตœ๋Œ€๊ณต์•ฝ์ˆ˜(GCD) ๊ตฌํ•˜๊ธฐ** + id:: 685d3d73-9ff0-4ec5-88b0-913cc9d52da5 + - ๋‘ ์ˆ˜ a,b๊ฐ€ ์žˆ์„ ๋•Œ, a๋ฅผ b๋กœ ๋‚˜๋ˆˆ ๋‚˜๋จธ์ง€๋ฅผ r์ด๋ผ ํ•˜๋ฉด a์™€ b์˜ ์ตœ๋Œ€๊ณต์•ฝ์ˆ˜๋Š” b์™€ r์˜ ์ตœ๋Œ€๊ณต์•ฝ์ˆ˜์™€ ๊ฐ™๋‹ค. + - ์ฆ‰ ์œ„์˜ ๊ณผ์ •์„ ๊ณ„์† ๋ฐ˜๋ณตํ•ด์„œ ๋‚˜๋จธ์ง€๊ฐ€ 0์ด ๋  ๋•Œ๊นŒ์ง€ ๋ฐ˜๋ณตํ•˜๋ฉด 0์ด๋˜๊ธฐ ์ง์ „์˜ ์ˆ˜๊ฐ€ ์ตœ๋Œ€ ๊ณต์•ฝ์ˆ˜๊ฐ€ ๋œ๋‹ค. + - ์ด๊ฒƒ์€ ๋ฐ˜๋ณต๋ฌธ์œผ๋กœ, ๋˜๋Š” ์žฌ๊ท€ํ•จ์ˆ˜๋กœ ๊ตฌํ•  ์ˆ˜ ์žˆ๋‹ค. + - ์˜ˆ์ œ์ฝ”๋“œ(ํŒŒ์ด์ฌ ๊ธฐ์ค€) + - ์žฌ๊ท€ํ•จ์ˆ˜๋กœ ๊ตฌํ˜„ + id:: 685d3e0d-40b4-4dd8-a43e-75ee4044f0a6 + - ```python + def GCD(a,b) : + x = max(a,b) + y = min(a,b) + if x%y == 0 : + return y + else : + return GCD(y, x%y) + + a = 18 + b = 24 + print(GCD(a,b)) # 6 + ``` + - ๋ฐ˜๋ณต๋ฌธ์œผ๋กœ ๊ตฌํ˜„ + id:: 685d3fbd-eaa7-438f-b0dc-ab5bfbe9acac + - ```python + a = 18 + b = 24 + + while b != 0: + r = a % b + a = b + b = r + + print(a) # 6 + + ``` + - **์ตœ์†Œ๊ณต๋ฐฐ์ˆ˜(LCM) ๊ตฌํ•˜๊ธฐ** + - ๋‘ ์ˆ˜ a,b์™€ ๊ทธ ์ˆ˜์˜ ์ตœ๋Œ€๊ณต์•ฝ์ˆ˜(GCD)๋ฅผ ์•Œ๋ฉด a,b์˜ ์ตœ์†Œ๊ณต๋ฐฐ์ˆ˜๋Š” ๋‹ค์Œ๊ณผ ๊ฐ™๋‹ค. + id:: 685d41ca-1832-434c-a919-0f67a2a37ec0 + - LCM = (a*b) / GCD(a,b) +- +- ## **ํŒŒ์ด์ฌ, ์ž๋ฐ”์Šคํฌ๋ฆฝํŠธ ๋ฐ˜๋ณต๋ฌธ ์ˆœํšŒ ๋ฐ ๊ฐ์ฒด/๋”•์…”๋„ˆ๋ฆฌ ์ˆœํšŒ** + - ### **โ–บ ์ผ๋ฐ˜์ ์ธ ๋ฐ˜๋ณต๊ฐ€๋Šฅ ๊ฐ์ฒด๋ฅผ ํ™œ์šฉํ•œ ๋ฐ˜๋ณต๋ฌธ ์ˆœํšŒ(๊ธฐ๋ณธ ์ˆœํšŒ)** + - **โ— pythron** + id:: 684e9cfd-e828-43ac-9f6c-76492bdcf94a + - ```python + arr = [1,2,3,4,5] + + for i in arr : + print(i) + + # ์ถœ๋ ฅ + # 1 2 3 4 5 + ``` + - **โ— javascript** + id:: 684e9d25-ddf8-4f7c-b781-21bb247497f8 + - ```javascript + const arr = [1,2,3,4,5]; + + for(let i of arr) { + console.log(i); + } + + // ์ถœ๋ ฅ + // 1 2 3 4 5 + ``` + - + - ### **โ–บ ์ž๋ฐ”์Šคํฌ๋ฆฝํŠธ์˜ ๊ฐ์ฒด(Object) ๋Š” ํŒŒ์ด์ฌ์˜ ๋”•์…”๋„ˆ๋ฆฌ(Dictionary)** + - **ํ‚ค(key)์™€ ๊ฐ’(value)์„ ๊ฐ€์ง€๋Š” ๋ฐ์ดํ„ฐ์˜ ์ง‘ํ•ฉ(๊ฐ๊ฐ์˜ ์–ธ์–ด์—์„œ ์„œ๋กœ ๋™์ผํ•˜๋‹ค๊ณ  ์ƒ๊ฐํ•ด๋„ ๋ฌด๋ฐฉํ•จ)** + - **โ—Ž ์„ ์–ธ ๋ฐ ์ ‘๊ทผ๋ฐฉ๋ฒ•** + - **โ— pythron** + id:: 684e9fb3-3cf0-4fa0-8539-e53bfe7fbcc1 + - ```python + # ๋นˆ๋ฐ์ดํ„ฐ ์ดˆ๊ธฐํ™” ๋ฐฉ๋ฒ• + dic = {} # dict() + + # ์ง์ ‘ ์„ ์–ธ ๋ฐฉ๋ฒ• + dic = { + "name": "Yechan", + "age" : 30 + } + + # ์ถœ๋ ฅ + print(dic["name"]) + print(dic["age"]) + # Yechan + # 30 + ``` + - **โ— javascript** + id:: 684ea0a5-0720-4a7b-a3b0-6fd81541ec05 + - ```javascript + // ๋นˆ๋ฐ์ดํ„ฐ ์ดˆ๊ธฐํ™” ๋ฐฉ๋ฒ• + let obj = {}; + + // ์ง์ ‘ ์„ ์–ธ ๋ฐฉ๋ฒ• + let obj = { + "name": "Yechan", + "age" : 30 + }; + + // ์ถœ๋ ฅ + console.log(obj.name); + console.log(obj["age"]); + // Yechan + // 30 + // ๋‘ ๋ฐฉ๋ฒ• ๋ชจ๋‘ ์‚ฌ์šฉ ๊ฐ€๋Šฅ + ``` + - **โ—Ž ํ‚ค ๋ฐ ๊ฐ’ ์ˆœํšŒ(๋ฐ˜๋ณต๋ฌธ ์‚ฌ์šฉ, ์ˆœ์„œ๋Š” ๋ณด์žฅ๋˜์ง€ ์•Š์Œ)** + - **โ— pythron** + id:: c506e90a-c84b-4498-ba5f-5028f5a874f6 + - ```python + dic = { + "name": "Yechan", + "age" : 30 + } + + # key ์ˆœํšŒ + for key in dic : + print(dic[key]) + # Yechan + # 30 + + # key, value ์ˆœํšŒ + for key, value in dic.items() : + print(key, value) + # name Yechan + # age 30 + ``` + - **โ— javascript** + id:: f380d0d7-7826-4714-bb8c-c78cc601ca50 + - ```javascript + let obj = { + "name": "Yechan", + "age" : 30 + }; + + // key ์ˆœํšŒ + for(let key in obj){ + console.log(obj[key]); + } + // Yechan + // 30 + + // key, value ์ˆœํšŒ + for [key, value] of Object.entries(obj) { + console.log(key, value); + } + // name Yechan + // age 30 + + for key of Object.keys(obj) { + console.log(key, obj[key]); + } + // name Yechan + // age 30 + ``` + - + - ### **โ–บ ํŒŒ์ด์ฌ์—์„œ ๋ฐ˜๋ณต๊ฐ€๋Šฅํ•œ ๋ฐ์ดํ„ฐ์…‹์˜ ๊ฐ’๊ณผ ์ธ๋ฑ์Šค๋ฅผ ๋ถˆ๋Ÿฌ์™€์„œ ์ˆœํšŒํ•˜๊ธฐ** + - **enumerate()** + id:: 6857c511-ce76-4075-ba45-a38956deb7df + - ๋ฐ˜๋ณต๊ฐ€๋Šฅํ•œ ๋ฐ์ดํ„ฐ์…‹์˜ ๊ฐ’๊ณผ ์ธ๋ฑ์Šค๋ฅผ ํŠœํ”Œํ˜•ํƒœ๋กœ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜ + id:: 6857c541-93f0-441f-8ff1-ca3cf8a3b186 + - ```python + arr = ["apple", "banana", "cat"] + for i in enumerate(arr) : + print(i) + # ์ถœ๋ ฅ + # (0, apple) + # (1, banana) + # (2, cat) + ``` + - ๋ฐ˜๋ณต๋ฌธ์—์„œ ์ธ๋ฑ์Šค์™€ ๊ฐ’์„ ๋™์‹œ์— ์ˆœํšŒํ•  ์ˆ˜ ์žˆ์Œ. + id:: 6857c6b6-3201-47a1-a090-c0ebe75d5e4c + - ```python + arr = ["apple", "banana", "cat"] + for index, value in enumerate(arr) : + print(index, value) + # ์ถœ๋ ฅ + # 0 apple + # 1 banana + # 2 cat + ``` + - ์‹œ์ž‘ ์ธ๋ฑ์Šค๋ฅผ ๋ฐ”๊ฟ€ ์ˆ˜๋„ ์žˆ์Œ. + id:: 6857c623-b8e4-4325-a8c2-27a9446118bd + - ```python + arr = ["apple", "banana", "cat"] + for index, value in enumerate(arr, start=1) : + print(index, value) + # ์ถœ๋ ฅ + # 1 apple + # 2 banana + # 3 cat + ``` + - +- +- ## **C์–ธ์–ด ๋ณ€์ˆ˜ ํƒ€์ž…๋ณ„ ๋ฉ”๋ชจ๋ฆฌ ํ• ๋‹นํฌ๊ธฐ ์ •๋ฆฌ** + - ### **๋นˆ์นธ ์ฑ„์›Œ๋ณด๊ธฐ** + id:: 684ea7e1-e59d-47a5-971f-2114a17fdda7 + - ![image.png](../assets/image_1749986661502_0.png) + id:: 684eae27-cd8a-4043-b999-d51b71757544 + - ![image.png](../assets/image_1749986614051_0.png) + id:: 684ea656-cac9-45ba-8dc4-5ade273c8777 +- +- ## **๋น„ํŠธ์—ฐ์‚ฐ ์ •๋ฆฌ** + - ### **XOR(๋ฐฐํƒ€์  ๋…ผ๋ฆฌํ•ฉ)** + - ๊ธฐํ˜ธ : ^ + id:: 684eaf61-54bb-4f69-af87-f75f280bd119 + - ์—ฐ์‚ฐ๊ฐ’ : (0,0)->0, (0,1)->1, (1,0)->1, (1,1)->0 [๊ฐ™์œผ๋ฉด 0, ๋‹ค๋ฅด๋ฉด 1] + id:: 684eafb2-7091-4d69-8c3f-0540d687b782 + - ํ•ต์‹ฌ์„ฑ์งˆ + id:: 684eaff6-5a2b-4cdd-ba5d-cba163b087fa + - ๊ฐ™์€ ๊ฐ’๋ผ๋ฆฌ XORํ•˜๋ฉด 0์ด ๋œ๋‹ค: `a ^ a = 0` + - 0๊ณผ XORํ•˜๋ฉด ์ž๊ธฐ ์ž์‹ ์ด ๋œ๋‹ค: `a ^ 0 = a` + - ๊ตํ™˜๋ฒ•์น™, ๊ฒฐํ•ฉ๋ฒ•์น™์ด ์„ฑ๋ฆฝํ•œ๋‹ค: `a ^ b = b ^ a`, `(a ^ b) ^ c = a ^ (b ^ c)` + - ํ™œ์šฉ + id:: 684eb038-f987-419b-b531-2b7a868c0842 + - ์ค‘๋ณต๋˜๋Š” ์—ฌ๋Ÿฌ ์ˆ˜๋“ค ์ค‘์— ๋‹จ ํ•˜๋‚˜ ๋‹ค๋ฅธ ์ˆ˜๋ฅผ ์ฐพ๋Š” ๋ฐฉ๋ฒ•์œผ๋กœ ํ™œ์šฉ + id:: 684eb045-4df8-4943-bdfb-65f983f2704e + - ๋ชจ๋“  ์ˆ˜๋ฅผ ํ•˜๋‚˜ํ•˜๋‚˜ xorํ•˜๋ฉด ๊ฒฐ๊ตญ ์ตœ์ข…์ ์œผ๋กœ ๋‚˜์˜ค๋Š” ๊ฒฐ๊ณผ๋Š” ๋‹ค๋ฅธ ํ•˜๋‚˜๊ฐ€ ๋‚˜์˜ด. + - ```C + int arr[] = {1, 2, 3, 2, 1}; + int res = 0; + for(int i=0; i<5; i++) res ^= arr[i]; + // res == 3 (์ง์ด ์—†๋Š” ๊ฐ’) + ``` + - ์ค‘๋ณต๋˜๋Š” ์ˆ˜๊ฐ€ ํ™€์ˆ˜๊ฐœ๋กœ ์ง์ง€์–ด์ ธ ์žˆ์œผ๋ฉด ์‚ฌ์šฉํ•  ์ˆ˜ ์—†์Œ + - ๋‹จ ๋‹จ ํ•˜๋‚˜์˜ ์ˆ˜๋ฅผ ์ œ์™ธํ•œ ๋ชจ๋“  ์ˆ˜๊ฐ€ ๊ฐ™์€ ์ˆซ์ž๋ผ๋ฉด ์‚ฌ์šฉ ๊ฐ€๋Šฅ + - ์ž„์‹œ๋ณ€์ˆ˜ ์—†์ด ๋‘ ๋ณ€์ˆ˜์˜ ๊ฐ’์„ swap + id:: 684eb1a1-f13d-45c3-b03b-da9372da5e7c + - XOR ์—ฐ์‚ฐ์˜ ์„ฑ์งˆ์„ ์ž˜ ์‘์šฉํ•˜๋ฉด ์•„๋ž˜์˜ ์ฝ”๋“œ์ฒ˜๋Ÿผ ๋‘ ๋ณ€์ˆ˜๋ฅผ ๊ตํ™˜ํ•  ์ˆ˜ ์žˆ์Œ. + - ```C + int a = 3; + int b = 5; + + a = a ^ b; + b = a ^ b; + a = a ^ b; + // ์ด์ œ a=5, b=3 (๊ฐ’์ด ์„œ๋กœ ๋ฐ”๋€œ) + ``` +- +- ## **์ž๋ฐ”์Šคํฌ๋ฆฝํŠธ ํŠน์ง•๊ด€๋ จ ๋‚ด์šฉ** + - **ํ™”์‚ดํ‘œ ํ•จ์ˆ˜** + - ์ •์˜ + id:: 685d3bc9-b9df-4cc9-be77-d6f26ee73924 + - ํ•จ์ˆ˜๋ฅผ funcion์œผ๋กœ ๋”ฐ๋กœ ์„ ์–ธํ•ด์„œ ์‚ฌ์šฉํ•˜๋Š” ๊ฒƒ์ด ์•„๋‹Œ ํ•œ์ค„, ํ˜น์€ ์—ฌ๋Ÿฌ์ค„๋กœ ๊ฐ„๊ฒฐํ•˜๊ฒŒ ํ‘œํ˜„ํ•˜๋Š” ํ‘œํ˜„์‹์˜ ํ•œ ํ˜•ํƒœ. + - ```javascript + // ๊ธฐ์กด ํ•จ์ˆ˜ ์„ ์–ธ ๋ฐฉ์‹ + function sum(a, b) { + return a+b; + } + + // ํ™”์‚ดํ‘œ ํ•จ์ˆ˜ + const sum = (a,b) => a+b; + ``` + - ์‚ฌ์šฉ๋ฐฉ๋ฒ• + id:: 685d3bec-8254-43a8-9d7a-fada78a05b6a + - ๋ณ€์ˆ˜ํƒ€์ž… ๋ฐ ํ•จ์ˆ˜๋ช…์„ ์“ฐ๊ณ  ๊ทธ ๋’ค์— =์„ ๋ถ™์ธ ๋’ค ๋ณ€์ˆ˜๋“ค์„ ๊ด„ํ˜ธ๋กœ ์ง€์ •ํ•œ ๋’ค => ๊ธฐํ˜ธ๋กœ ์—ฐ๊ฒฐ. + - ์ด ํ›„ ํ™”์‚ดํ‘œ ๋’ค์— ํ•จ์ˆ˜๋ฅผ ์ ์œผ๋ฉด ๋จ. + - ์ด ๋’ค์˜ ํ•จ์ˆ˜๊ฐ€ ํ•œ์ค„์ด๋ฉด return์„ ์“ฐ์ง€ ์•Š์•„๋„ ์•Œ์•„์„œ ๋ฐ˜ํ™˜ํ•จ. + - ์—ฌ๋Ÿฌ์ค„ ์ผ ๊ฒฝ์šฐ์—๋Š” ์ค‘๊ด„ํ˜ธ๋ฅผ ์“ฐ๊ณ , ์ด๋•Œ๋Š” ๊ผญ return์„ ์จ์ค˜์•ผ ํ•จ. + - ```javascript + // ํ•œ ์ค„, ์•”์‹œ์  ๋ฐ˜ํ™˜ + const sum = (a, b) => a + b; + + // ์—ฌ๋Ÿฌ ์ค„, ๋ช…์‹œ์  ๋ฐ˜ํ™˜ ํ•„์š” + const multiply = (a, b) => { + const result = a * b; + return result; + }; + ``` + - ์˜ˆ์‹œ์ฝ”๋“œ + - ํ•œ ์ค„๋กœ ํ‘œํ˜„, ์ž…๋ ฅ๊ฐ’์˜ 2๋ฐฐ๋ฅผ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜ ์„ ์–ธ + id:: 685d3c87-2b8e-410e-87f6-9166619ab636 + - ```javascript + const double = x => x*2; + + console.log(double(10)); // 20 + ``` + - ์—ฌ๋Ÿฌ์ค„ ํ‘œํ˜„, ๋‘ ์ˆ˜๋ฅผ ์ž…๋ ฅ๋ฐ›์•„์„œ ๊ทธ ๋‘ ์ˆ˜๋ฅผ ๊ณฑํ•œ ๊ฐ’์„ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜ ์„  + id:: 685d3cd9-6924-4800-a57d-61f5d37193db + - ```javascript + const multiply = (a,b) => { + const result = a*b; + return result; + }; + + console.log(multiply(10,5)); // 50 + ``` \ No newline at end of file diff --git a/pages/๐Ÿ“‹ Index Page.md b/pages/๐Ÿ“‹ Index Page.md index 5729742..1a212d0 100644 --- a/pages/๐Ÿ“‹ Index Page.md +++ b/pages/๐Ÿ“‹ Index Page.md @@ -1,3 +1,4 @@ - [[๐Ÿ”ค ์˜์–ด๊ณต๋ถ€]] - [[๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ]] +- [[๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ป์ฝ”๋”ฉ ํŒ ์ฝ”๋“œ ๋ชจ์Œ_์ด์ „]] - \ No newline at end of file