寻找最短路径

#S######.#
......#..#
.#.##.##.#
.#........
##.##.####
....#....#
.#######.#
....#.....
.####.###.
....#...G#

//找出最短路径是多少

#include<iostream>  
#include<queue>
#include <utility>
using namespace std;
const int INF = 100000000;
typedef pair<int, int> P;
char maze[100][100];
int N, M;
int sx=0, sy=1;
int gx=9, gy=8;
int d[100][100];
int dx[4] = { 1,0,-1,0 }, dy[4] = { 0,1,0,-1 };
int bfs()
{
    queue<P>que;
    for (int i = 0; i < N; i++)
        for (int j = 0; j < M; j++) d[i][j] = INF;
    que.push(P(sx, sy));
    d[sx][sy] = 0;

    while (!que.empty())
    {
        P k = que.front(); que.pop();
        if (k.first == gx && k.second == gy) break;
        
        for (int i = 0; i < 4; i++)
        {
            int nx = k.first + dx[i], ny = k.second + dy[i];

            if (0 <= nx && nx < N && 0 <= ny && ny < M&&maze[nx][ny] != '#'&&d[nx][ny] == INF)
            {
                que.push(P(nx, ny));
                d[nx][ny] = d[k.first][k.second] + 1;
            }
        }
    }
    return d[gx][gy];
}
int main()
{
    N = 10, M = 10;
    for (int i = 0; i < N; i++)
        for (int j = 0; j < M; j++)
            cin >> maze[i][j];
    int res = bfs();
    cout << res << endl;
    return 0;
}

//宽度优先比深度复杂一些