ex9

#include<iostream>
using namespace std;
int main()
{
    int n,i,j,a[25][25],sus=1,stanga=1,jos,dreapta,k=1;
    cin>>n;
    jos=n;
    dreapta=n;
    while(stanga<dreapta)
    {
        for(j=stanga; j<=dreapta; j++)  { a[sus][j]=k; }
        sus++;
        for(i=sus; i<=jos; i++) {a[i][dreapta]=k;}
        dreapta--;
        for(j=dreapta; j>=stanga; j--) {a[jos][j]=k;}
        jos--;
        for(i=jos; i>=sus; i--) {a[i][stanga]=k;}
        stanga++;
        k=!k;
    }
    for(i=1; i<=n; i++)
    {
        for(j=1; j<=n; j++)
            cout<<a[i][j]<<" ";
        cout<<endl;
    }
}