2021-08-21 AcWing第13场周赛 3812. 机器人走迷宫

  暴力+全排列

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输入样例：

2
5 6
.....#
S....#
.#....
.#....
...E..
333300012
6 6
......
......
..SE..
......
......
......
01232123212302123021

输出样例：

1
14

#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>

using namespace std;

int m,n;
char a[51][51];
string path;
bool check(vector<int>& turn)
{
    int x0,y0;
    int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, 1, 0, -1};
    for (int i = 0; i < m; i ++ )
        for (int j = 0; j < n; j ++ )
            if(a[i][j]=='S') y0 = i, x0 = j;
    
    for(auto ch: path)
    {
        int k = turn[ch-'0'];
        x0 += dx[k], y0 += dy[k];
        if(x0<0 || y0<0 || y0>=m || x0>=n || a[y0][x0]=='#')
            return false;
        if(a[y0][x0]=='E')
            return true;
    }
    return false;
}

int main()
{
    int t;
    cin >> t;
    while (t -- )
    {
        cin >> m >> n;
        for (int i = 0; i < m; i ++ ) cin >> a[i];
        
        cin >> path;
        int res=0;
        vector<int> turn{0, 1, 2, 3};
        for (int i = 0; i < 24; i ++ ){
            if(check(turn))
                res++;
            next_permutation(turn.begin(),turn.end());//以此更换每轮0123与上下左右的对应关系
        }
        cout << res << endl;
    }
    return 0;
}