<span style="font-family:Courier New;font-size:18px;">#include <iostream>
using namespace std;

const int maxn=20;
int a[maxn][maxn];

void draw(int x,int y,int start,int size)
{
    if(size<=0) return;
    int t1=x,t2=y;
    for(int i=x;i<t1+size-1;i++){
        a[i][y]=start;
        start++;
    }
    x=t1+size-1;

    for(int j=y;j<t2+size-1;j++) {
        a[x][j]=start;
        start++;
    }
    y=t2+size-1;

    for(int i=x;i>t1;i--) {
        a[i][y]=start;
        start++;
    }
    x=t1;

    for(int j=y;j>t2;j--) {
        a[x][j]=start;
        start++;
    }
    x=t1+1;
    y=t2+1;
    draw(x,y,start,size-2);
}
int main()
{
    int n;
    cin>>n;
    draw(0,0,1,n);
    for(int i=0;i<n;i++) {
        for(int j=0;j<n;j++) {
            cout<<a[i][j]<<" ";
        }
        cout<<endl;
    }
    return 0;
}</span>