add leetcode 1143.cpp

Author: BWbwchen

leetcode/1143.cpp

@@ -0,0 +1,18 @@
+class Solution {
+public:
+    int longestCommonSubsequence(string text1, string text2) {
+        vector<vector<int>> dp(text1.size()+1, vector<int>(text2.size()+1, 0));
+        // dp[i][j] = LCS of text1[0..i] and text2[0..j]
+        for (int i = 1; i <= text1.size(); ++i) {
+            for (int j = 1; j <= text2.size(); ++j) {
+                if (text1[i-1] == text2[j-1]) {
+                    dp[i][j] = dp[i-1][j-1] + 1;
+                } else {
+                    dp[i][j] = max(dp[i-1][j], dp[i][j-1]); 
+                }
+            }
+        }
+        
+        return dp[text1.size()][text2.size()];
+    }
+};