Răspuns:
#include <iostream>
using namespace std;
int main()
{ int a[100][100],n,i,j;
cout<<"n=";cin>>n;
for(i=1;i<=n;i++)
for(j=1;j<=n;j++)
if(i+j==n+1)
a[i][j]=0;
else
a[i][j]=i;
for(i=1;i<=n;i++)
{for(j=1;j<=n;j++)
cout<<a[i][j]<<" ";
cout<<endl;}
return 0;
}
Explicație: Sper ca ajuta