diff --git a/code_study/Baekjoon/python/12015.py b/code_study/Baekjoon/python/12015.py
new file mode 100644
index 0000000..edc2390
--- /dev/null
+++ b/code_study/Baekjoon/python/12015.py
@@ -0,0 +1,22 @@
+N, A = int(input()), list(map(int, input().split()))
+
+LIS = []
+
+for a in A :
+    if not len(LIS) or a > LIS[-1] :
+        LIS.append(a)
+        
+    else :
+        left, right = 0, len(LIS) - 1
+        
+        while left < right :
+            mid = (left + right) // 2
+            
+            if a > LIS[mid] :
+                left = mid + 1
+            else :
+                right = mid
+        
+        LIS[left] = a
+            
+print(len(LIS))
\ No newline at end of file
diff --git a/code_study/Baekjoon/python/15015_1.py b/code_study/Baekjoon/python/15015_1.py
new file mode 100644
index 0000000..30075ff
--- /dev/null
+++ b/code_study/Baekjoon/python/15015_1.py
@@ -0,0 +1,15 @@
+from bisect import bisect_left
+
+N = int(input())
+A = list(map(int, input().split()))
+
+LIS = []
+
+for a in A :
+    if not len(LIS) or a > LIS[-1]:
+        LIS.append(a)
+    else:
+        idx = bisect_left(LIS, a)
+        LIS[idx] = a
+
+print(len(LIS))
\ No newline at end of file
diff --git a/code_study/Baekjoon/python/2914.py b/code_study/Baekjoon/python/2914.py
new file mode 100644
index 0000000..af85e27
--- /dev/null
+++ b/code_study/Baekjoon/python/2914.py
@@ -0,0 +1 @@
+print((lambda A, I: A*(I-1)+1)(*list(map(int, input().split()))))
\ No newline at end of file