题目传送门

#include<bits/stdc++.h>
using namespace std;
int a,b,n,ans,temp=1,m;
bool f;
char k;
int main(){
	
	cin>>n>>m>>k>>f;
	for(int i=1;i<=n;i++){
		cout<<k;
		for(int j=2;j<m;j++){
			if(f||i==1||i==n) cout<<k;
			else cout<<" ";
		}
		cout<<k<<endl;
	
	}
	//cout<<ans<<endl;
	return 0;
}