class Solution {
public:
int longestCommonSubsequence(string text1, string text2) {
        int l1 = (int) text1.length();
        int l2 = (int) text2.length();
        int f[l1+1][l2+1];

        for (int i=0; i<=l1; i++){
            f[i][0] = 0;
        }
        for (int j=0; j<=l2; j++){
            f[0][j] = 0;
        }
        for (int i=1; i<=l1; i++) {
            for (int j = 1; j<=l2; j++) {
                if (text1[i-1]==text2[j-1]) {
                    f[i][j] = 1 + f[i-1][j-1];
                } else {
                    f[i][j] = max(f[i-1][j],f[i][j-1]);
                }
            }
        }
        return f[l1][l2];
}
};