//Serene
#include<algorithm>
#include<iostream>
#include<cstring>
#include<cstdlib>
#include<cstdio>
#include<cmath>
using namespace std;
const int maxn=50+5;
int n;
int main() {
cin>>n;
while(n) {
if(n<=3) printf("1\n");
else if(n==4) printf("2\n");
else printf("%d\n",n);
cin>>n;
}
return 0;
}
原文：http://www.cnblogs.com/Serene-shixinyi/p/7612858.html