#include<cstdio>
void xsprint(int x,int y,int num);
void xprint(int x,int y);
void xxprint(int x,int y,int num);
void zprint(int x,int y);
int a[501][501];
int m,n;
int flag;
int main()
{

	scanf("%d",&n);
	for(int i=0;i<n;i++)
	{
		for(int j=0;j<n;j++)
		scanf("%d",&a[i][j]);
	}
	printf("%d",a[0][0]);
	zprint(0,0);
}
void xsprint(int x,int y)
{   if(x>=n&&y>=n)
	return;
	for(int i=1;;i++)
	{
	if(y+i>=n||x-i<0)
	{
	flag=i-1;
	zprint(x-flag,y+flag);
	return ;
     }
     else
	 printf(" %d",a[x-i][y+i]);
     }

}
void xprint(int x,int y)
{
	if(x+1>=n&&y+1>=n)
	return;
	else if(x+1>=n)
	{
	  printf(" %d",a[x][y+1]);
	  xsprint(x,y+1);
	  return;
	}
	else
	{
		printf(" %d",a[x+1][y]);
	    xsprint(x+1,y);
	}
}
void xxprint(int x,int y)
{  	if(x>=n&&y>=n)
    return;
	for(int i=1;;i++)
	{
	 if(x+i>=n||y-i<0)
	 {
	 flag=i-1;
	 xprint(x+flag,y-flag);
	 return;
     }
     else
	 printf(" %d",a[x+i][y-i]);
    }

}
void zprint(int x,int y)
{

	if(y+1>=n&&x+1>=n)
	return;
	else if(y+1>=n)
	{
	printf(" %d",a[x+1][y]);
	xxprint(x+1,y);
	}
	else
	{
		 printf(" %d",a[x][y+1]);
	     xxprint(x,y+1);
	}
}