#include <bits/stdc++.h>
using namespace std;
int n,a[35][35],b[35][35];
void find(int i,int j){
	if(a[i][j]||b[i][j]||i<1||i>n||j<1||j>n) return;//越界检测 
	b[i][j]=1;//访问标记 
	find(i-1,j);find(i+1,j);
	find(i,j+1);find(i,j-1); 
}
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			cin>>a[i][j];
			if(a[i][j]==0) b[i][j]=0;
			else b[i][j]=1;
		}
	}
	find(0,0);
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			if(a[i][j]==0) cout<<"2 ";
			else cout<<b[i][j]<<" ";
		}
		cout<<endl;
	}
	return 0;
}

把外圈“0”怎么变回来 只做了把所有“0”都刷成“2”了