feat: maximum-product-subarray

Author: minji-go

maximum-product-subarray/minji-go.java

@@ -0,0 +1,26 @@
+/**
+ * <a href="https://leetcode.com/problems/maximum-product-subarray/">week9-3. maximum-product-subarray</a>
+ * <li>Description: Given an integer array nums, find a subarray that has the largest product, and return the product. </li>
+ * <li>Topics: Array, Dynamic Programming       </li>
+ * <li>Time Complexity: O(N), Runtime 2ms       </li>
+ * <li>Space Complexity: O(1), Memory 45.42MB   </li>
+ */
+class Solution {
+    public int maxProduct(int[] nums) {
+        int maxSoFar = nums[0];
+        int minSoFar = nums[0];
+        int result = nums[0];
+
+        for (int i = 1; i < nums.length; i++) {
+            int cur = nums[i];
+            int tempMax = maxSoFar;
+
+            maxSoFar = Math.max(cur, Math.max(cur * maxSoFar, cur * minSoFar));
+            minSoFar = Math.min(cur, Math.min(cur * tempMax, cur * minSoFar));
+
+            result = Math.max(result, maxSoFar);
+        }
+
+        return result;
+    }
+}