#include<bits/stdc++.h>
using namespace std;

int Phi(int n)
{
    double nn=n;
    vector<double> v;
    int ok=0;
    while(n%2==0)
        n/=2,ok=1;
    if(ok==1)
        v.push_back(2);
    for(int i=3;i<=sqrt(n);i+=2)
    {
        ok=0;
        while(n%i==0)
            n/=i,ok=1;
        if(ok==1)
            v.push_back(i);
    }
    if(n>2)
        v.push_back(n),n/=n;
    for(int i=0;i<v.size();i++)
        nn*=(1-1/v[i]);
    return nn;
}