1 2 #include<stdio.h> 3 int main() 4 { 5 int n; 6 while(scanf("%d",&n),n) 7 { 8 int s=0,m,t; 9 while(n>2) 10 { 11 t=n%3; 12 m=n/3; 13 s+=m; 14 n=m+t; 15 } 16 if(n==2) 17 s++; 18 printf("%d\n",s); 19 } 20 } 21