一个以前没见过的CE

#include<bits/stdc++.h>
using namespace std;
const int mn = 10;
int a[1<<mn+10][1<<mn+10];
int n,j,i,p,q;
void sm(int x,int y,int m){
    if(m>=1){
    for(p = x;p<=x+1<<(m-1)-1;p++)
        for(q = y;q<=x+1<<(m-1)-1;q++)
            a[p][q] = 0;
    sm(x+1<<(m-1),y,m-1);
    sm(x,y+1<<(m-1),m-1);
    sm(x+1<<(m-1),y+1<<(m-1),m-1);
    }
    return;
}
int main(){
    cin>>n;
    for(i  = 1;i<=1<<n;i++)
        for(j = 1;j<=1<<n;j++)
            a[i][j] = 1;
    sm(1,1,n);
    for(i  = 1;i<=1<<n;i++){
        for(j = 1;j<=1<<n;j++)
            cout<<a[i][j]<<' ';
        cout<<endl;
    }
    return 0;
}