#include<stdio.h>
int main()
{
    int n;
    scanf("%d",&n);
    if(n<0 || n> 10)
    {
        printf("Invalid Input");
        return 0;
    }
    int size =2*n-1;
    for (int i=0; i<size;i++)
    {
        for(int j=)
        int min=1<j?i;j;
        if(size-1-i<min)
        min=size-1-i;
        if(size-1-j<min)
        min=size-1-j;
        printf("%d",n-min);
    }
    printf("\n");
}