for (int i = 0; i < n; i++) C[i][0] = 0;
for (int j = 0; j < m; j++) C[0][j] = 0;

    for (inr i = 1; i < n; i++)
        for (int j = 1; j < m; j++)
        {
            if (A[i] == B[j]) C[i][j] = C[i-1][j-1] + 1;
            else C[i][j] = max(C[i-1][j], C[i][j-1]);
        }