安排比赛

// An highlighted block

#include<stdio.h>
#include<iostream>
using namespace std;
int main(){
	int sum,k,l;
	int n[100000];
	int i=0,j;
	while(1){
		scanf("%d",&n[i]);
		if(n[i]==0) break;
		i++;
	}
	for(j=0;j<i;j++){
		k=n[j];sum=0;l=0;
		while(k>=3){
			l=k%3;
			k=k/3;
			sum+=k;
			k+=l;
		}
		if(k>1)
			sum++;
		cout<<sum<<"\n";
	}
	return 0;
}