#include <iostream>
using namespace std;
int main()
{int n,i,j,a[101][101];
cin>>n;
for (i=1;i<=n;i++)
for (j=1;j<=n;j++)
if (i==j)
a[i][j]=1;
else a[i][j]=0;
for (i=1;i<=n;i++)
{for (j=1;j<=n;j++)
cout<<a[i][j]<<" ";
cout<<endl;
}
return 0;
}
ce-am facut: o matrice in care elementele de pe diagonala principala sunt 1, iar restul 0. indeplineste cerinta.