#include<bits/stdc++.h> using namespace std; int main(){ int i,j,n,c=1,a[20][20]={0}; cin>>n; for(i=0;i<n;i++){ a[i][i]=1; } for(i=0;i<n;i++){ for(j=0;j<n;j++){ cout<<setw(3)<<a[i][j]; } cout<<endl; } return 0; } /************************************************************** Problem: 1190 User: wangzherongyao Language: C++ Result: Accepted Time:9 ms Memory:2072 kb ****************************************************************/