class Solution {
public:
    int longestCommonSubsequence(string text1, string text2) {
        int m = text1.size();
        int n = text2.size();
        vector<vector<int>> f(m+1, vector<int>(n+1));
        for (int i = 1; i <= m; ++i) {
            for (int j = 1; j <= n; ++j) {
                f[i][j] = max(f[i-1][j], f[i][j-1]);
                if (text1[i-1] == text2[j-1]) {
                    f[i][j] = max(f[i][j], f[i-1][j-1]+1);
                }
            }
        }
        return f[m][n];
    }
};