正经题解-DFS模板

不会的直接背，反正这些题都大差不差（

#include <bits/stdc++.h>
using namespace std;
int n, m;
int vis[100][100];
int dx[4] = {0, 0, -1, 1};
int dy[4] = {-1, 1, 0, 0};
char a[100][100];
void dfs(int x, int y) {
    vis[x][y] = 1;
    if (x == n - 1 && y == m - 1) {
        cout << "YES";
        exit(0);
    } for (int i = 0; i < 4; i++) {
        int nx = x + dx[i];
        int ny = y + dy[i];
        if (nx >= 0 && nx < n && ny >= 0 && ny < m && vis[nx][ny] == 0 && a[nx][ny] == '0') {
            dfs(nx, ny);
        }
    }
    return;
}
int main() {
    cin >> n >> m;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) cin >> a[i][j];
    }    
    dfs(0, 0);
    cout << "NO";
    return 0;
}