baekjoon 20260415

code_study/Baekjoon/python/1509.py

@@ -1,30 +1,27 @@
-s = input().rstrip()
-l = len(s)
+S = input().rstrip()
+L = len(S)
 
-isPalindrom = [[False]*l for _ in range(l)]
-for length in range(1,l+1) :
-    for start in range(l-length + 1) :
-        end = start + length - 1
+isPal = [[False]*L for _ in range(L)]
+for i in range(L) :
+    isPal[i][i] = True
+    if i != 0 and S[i] == S[i-1] :
+        isPal[i-1][i] = True
 
-        if length == 1 :
-            isPalindrom[start][end] = True
+for l in range(3, L+1) :
+    for start in range(L-l+1) :
+        end = start + l - 1
         
-        elif length == 2 :
-            if s[start] == s[end] :
-                isPalindrom[start][end] = True
-        else :
-            if s[start] == s[end] and isPalindrom[start+1][end-1]:
-                isPalindrom[start][end] = True
+        if S[start] == S[end] and isPal[start+1][end-1] :
+            isPal[start][end] = True
 
-dp = [2501]*l
+dp = [L+1] * L
 
 for end in range(l) :
     for start in range(end+1) :
-        if isPalindrom[start][end] :
+        if isPal[start][end] :
             if start == 0 :
                 dp[end] = 1
             else :
                 dp[end] = min(dp[end], dp[start-1] + 1)
 
-print(dp[l-1])
-        
+print(dp[L-1])

code_study/Baekjoon/python/2443.py

@@ -0,0 +1 @@
+print("\n".join([" "*i + "*"*(2*N-(2*i+1)) for N in [int(input())] for i in range(N)]))