Add longest-increasing-subsequence solution

Author: Jeehay28

longest-increasing-subsequence/Jeehay28.js

@@ -0,0 +1,26 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+
+// Time Complexity: O(n^)
+// Space Complexity: O(n)
+var lengthOfLIS = function (nums) {
+  if (nums.length === 0) {
+    return 0;
+  }
+
+  let dp = new Array(nums.length).fill(1); // dp[i] will be the length of LIS ending at i
+
+  for (let i = 1; i < nums.length; i++) {
+    for (let j = 0; j < i; j++) {
+      if (nums[i] > nums[j]) {
+        // Strictly increasing condition
+        dp[i] = Math.max(dp[i], dp[j] + 1);
+      }
+    }
+  }
+
+  return Math.max(...dp); // The length of the longest subsequence
+};
+