class Solution {
public:
    int f(int i, int j, int steps, vector<vector<int>>& grid, vector<vector<int>>& dp) {
        int n = grid.size();
        int m = grid[0].size();


        if (i >= n || j >= m) {
            return 1e9;
        }

        if (i == n - 1 && j == m - 1) {
            return steps;
        }

        if (dp[i][j] != -1) {
            return dp[i][j];
        }

        int ans = 1e9;

        for (int right = j + 1; right <=j + grid[i][j]; right++) {
            ans = min(ans, f(i, right, steps + 1, grid, dp));
        }

        for (int down = i + 1; down <= i + grid[i][j]; down++) {
            ans = min(ans, f(down, j, steps + 1, grid, dp));
        }
        return dp[i][j] = ans;
    }

    int minimumVisitedCells(vector<vector<int>>& grid) {
        int n = grid.size();
        int m = grid[0].size();

        vector<vector<int>> dp(n, vector<int>(m, -1));

        int ans = f(0, 0, 1, grid, dp);
        return (ans >= 1e9) ? -1 : ans;
    }
};