maximum-subarray solution (py)

Author: hi-rachel

maximum-subarray/hi-rachel.py

@@ -0,0 +1,36 @@
+# 최대 부분 배열 합 문제
+
+# O(n^2) time, O(1) space
+# Time Limit Exceeded
+
+class Solution:
+    def maxSubArray(self, nums: List[int]) -> int:
+        max_total = nums[0]
+        for i in range(len(nums)):
+            total = 0
+            for j in range(i, len(nums)):
+                total += nums[j]
+                max_total = max(total, max_total)
+        return max_total
+    
+# 개선 풀이
+# O(n) time, O(1) space
+class Solution:
+    def maxSubArray(self, nums: List[int]) -> int:
+        max_total = nums[0]
+        total = nums[0]
+        for i in range(1, len(nums)):
+            total = max(nums[i], total + nums[i])
+            max_total = max(total, max_total)
+        return max_total 
+
+# DP 풀이
+# O(n) time, O(n) space
+class Solution:
+    def maxSubArray(self, nums: List[int]) -> int:
+        dp = [0] * len(nums)
+        dp[0] = nums[0]
+        for i in range(1, len(nums)):
+            dp[i] = max(nums[i], dp[i - 1] + nums[i])
+        return max(dp)
+