蓝桥杯迷宫题 遇到了错误，不知道是哪里写错了，用的是DFS思路，图里面那个简单的用例

Question

蓝桥杯迷宫题

##遇到了错误，不知道是哪里写错了，用的是DFS思路，图里面那个简单的用例

#include<bits/stdc++.h>
using namespace std;
int tox[] = {1,0,0,-1};
int toy[] = {0,-1,1,0};
char dir[] = {'D','L','R','U'};

const int row = 4;
const int col = 6;
string maze[row]={
   "010000",
   "000100",
   "001001",
   "110000"
};
int mins[row+5][col+5];
int best = 1e8+5;
char a[row*col];
string ans;
string temp;

void dfs(int x , int y , int step){
   if(step > best) return;
   if(x == row - 1 && y == col - 1) {
       for(int i=1;i<step;i++)
           temp+=a[i];
       if(step < best)
           best = step;
           ans = temp;
       return;
   }
   else if(step==best && temp<ans)    ans=temp;
   for(int i = 0 ; i < 4 ; i++){
       int nextx = x + tox[i];
       int nexty = y + toy[i];
       if(nextx >= 0 && nextx <= row - 1 && nexty >= 0 && nexty <= col - 1 && maze[nextx][nexty]=='0' && step + 1 <= mins[nextx][nexty]){
           mins[nextx][nexty] = step +1;
           maze[nextx][nexty] = '1';
           a[step] = dir[i];
           dfs(nextx , nexty , step+1);
           maze[nextx][nexty] = '0';
       }
   }
}

int main(){
   memset(mins,1,sizeof(mins));
   maze[0][0] = '1';
   dfs(0, 0 ,0);
   cout<< best<<endl;
   cout<< ans;
   return 0;
}

##正确答案应该是