Add leetcode 300

LeetCode-CN/300.cpp

@@ -0,0 +1,19 @@
+class Solution {
+public:
+    int lengthOfLIS(vector<int>& nums) {
+        int N = nums.size();
+        vector<int> dp(N);
+        for (int i = 0; i < N; i++) {
+            dp[i] = 1;
+        }
+        for (int i = 1; i < N; i++) {
+            for (int j = 0; j < i; j++) {
+                if (nums[i] > nums[j]) {
+                    dp[i] = max(dp[i], dp[j] + 1);
+                }
+            }
+        }
+
+        return *max_element(dp.begin(), dp.end());
+    }
+};