_```cpp #include<bits/stdc++.h> using namespace std; int n,m,way[1010101][2]; int mx[5]={0,0,1,0,-1},my[5]={0,-1,0,1,0}; int map1[16][16],l; int zhon,dian,ans=0; void dfs(int x,int y){ if(x==zhon&&y==dian){ cout<<l<<endl; for(int i=1;i<=l;i++){ cout<<"("<<way[i][1]<<","<<way[i][2]<<")->"; } cout<<endl; l=0; ans++; return ; } for(int i=1;i<=4;i++){ if(map1[x+my[i]][y+mx[i]]==0&&y+mx[i]<m&&x+my[i]<n&&x+my[i]>0&&y+mx[i]>0){ cout<<x+my[i]<<" "<<y+mx[i]<<endl; map1[x+my[i]][y+mx[i]]=1; l++; dfs(x+my[i],y+mx[i]); l--; map1[x+my[i]][y+mx[i]]=0; } } } int main(){ cin>>n>>m; for(int i=1;i<=n;i++){ for(int j=1;j<=m;j++){ cin>>map1[i][j]; } } int x,y; cin>>x>>y>>zhon>>dian; dfs(x,y); if(ans==0){ cout<<-1; } }

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