/*
  AOJ 1027
  Title:
  @kankichi573
*/
#include <stdio.h>
int K,c;


main()
{
        int i,sum;

        while(EOF!=scanf("%d",&K) && K)
        {
                for(i=0,sum=0;i<K*(K-1)/2;i++)
                {
                        scanf("%d ",&c);
                        sum += c;
                }
                printf("%d\n",sum/(K-1));
        }
        return(0);
}