best path

#include <bits/stdc++.h>
using namespace std;
// best path
const int N = 100;
int a[N][N];
int n, m;
bool valid (int row, int col) {
    return (row >= 0 && col >= 0 && row < n && col < m);
}
int best_path (int row, int col) {
    if (!valid(row, col))
        return false;
    if(row == n - 1 && col == m - 1)
        return a[row][col];
    int path1 = best_path(row + 1, col);
    int path2 = best_path(row, col + 1);
    return a[row][col] + max(path1, path2);
}
int main () {
//    freopen("/home/hamoudi/clion/hello.in", "rt", stdin);
    cin >> n >> m;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            cin >> a[i][j];
        }
    }
    cout << best_path(0, 0) << '\n';
}