poj2407 欧拉函数

#include<iostream>using namespace std;int eular(int n){int rea=n;for(int i=2;i*i<=n;i++)if(n%i==0){rea-=rea/i;while(n%i==0){n/=i;}}if(n>1)rea-=rea/n;return rea; } int main(){int n;while(scanf("%d",&n)!=EOF && n){printf("%d\n",eular(n));}return 0;}