#include<bits/stdc++.h>
using namespace std;
int a[0];
int main(){
	int n;
	cin>>n;
	cout<<n<<endl;
	for (int i = 1; i <= n; i++){
		for (int j = 1; j <= n; j++){
			if(i != j){
				if(a[j]) a[j] = 0;
				else a[j] = 1;
			}
			cout<<a[j];
		}
		cout<<endl;
	}
	return 0;
}

题目说n <= 100并且是偶数 结果AC?：int a[0];