Add maximum-product-subarray solution in TS

Author: Jeehay28

maximum-product-subarray/Jeehay28.ts

@@ -0,0 +1,40 @@
+// TC: O(n)
+// SC: O(1)
+function maxProduct(nums: number[]): number {
+  let prevMax = nums[0];
+  let prevMin = nums[0];
+  let maxProd = nums[0];
+
+  for (let i = 1; i < nums.length; i++) {
+    const currentNum = nums[i];
+    const tempMax = Math.max(
+      currentNum,
+      prevMax * currentNum,
+      prevMin * currentNum
+    );
+    prevMin = Math.min(currentNum, prevMax * currentNum, prevMin * currentNum);
+    prevMax = tempMax;
+    maxProd = Math.max(maxProd, prevMax);
+  }
+
+  return maxProd;
+}
+
+
+// TC: O(n^2)
+// SC: O(1)
+// function maxProduct(nums: number[]): number {
+//   let largestProd = -Infinity;
+//   let subProd = 1;
+
+//   for (let i = 0; i < nums.length; i++) {
+//     subProd = 1;
+//     for (let j = i; j < nums.length; j++) {
+//       subProd *= nums[j];
+//       largestProd = Math.max(largestProd, subProd);
+//     }
+//   }
+
+//   return largestProd;
+// }
+