막힌 칸을 피하는 경로 수

#include <iostream>
#include <vector>
using namespace std;

int solution(vector<vector<int>> board) {
    const int MOD = 1000000007;
    int rows = (int)board.size();
    int cols = (int)board[0].size();
    vector<vector<int>> dp(rows + 1, vector<int>(cols + 1, 0));
    dp[0][1] = 1;
    for (int r = 1; r <= rows; ++r) {
        for (int c = 1; c <= cols; ++c) {
            if (board[r - 1][c - 1] == 1) {
                dp[r][c] = dp[r - 1][c];
            } else {
                dp[r][c] = (dp[r - 1][c] + dp[r][c - 1]) % MOD;
            }
        }
    }
    return dp[rows][cols];
}
int main() {
    int rows, cols;
    cin >> rows >> cols;
    vector<vector<int>> board(rows, vector<int>(cols));
    for (int r = 0; r < rows; ++r)
        for (int c = 0; c < cols; ++c) cin >> board[r][c];
    cout << solution(board) << '\n';
}