re玄关

#include<bits/stdc++.h>
using namespace std;

struct xy
{
    int x;
    int y;
};

int f[105][105];

int dx[12]={0,0,1,-1};
int dy[12]={1,-1,0,0};

int n; 

int bfs(int x,int y)
{
    queue<xy> q;
    xy noww,nextt;
    noww.x=x;
    noww.y=y;

    f[x][y]=1;
    q.push(noww);
    while(!q.empty())
    {
        noww=q.front();
        q.pop();

        for(int i=0;i<4;i++)
        {
            nextt.x=noww.x+dx[i];
            nextt.y=noww.y+dy[i];
            if(nextt.x>=1&&nextt.x<=n&&nextt.y>=1&&nextt.y<=n&&!f[nextt.x][nextt.y])
            {
                f[nextt.x][nextt.y]=2;
                q.push(nextt);
            }
        }
    }
}
int main()
{
    for(int i=0;i<=31;i++)
    {
        f[i][0]=0;
        f[i][31]=0;
        f[31][i]=0;
        f[0][i]=0;
    }
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=n;j++)
        {
            cin>>f[i][j];
        }
    }
    bfs(0,0);
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=n;j++)
        {
            if(f[i][j]==2)
            {
                cout<<"0 ";
            }
            else if(f[i][j]==0)
            {
                cout<<"2 ";
            }
            else
            {
                cout<<"1 ";
            }
        }
        cout<<'\n';
    }
    return 0;
}