Cod sursa(job #3262646)

Utilizator Alexandru_cioAlexandru Ciobanica Alexandru_cio Data 11 decembrie 2024 09:25:52
Problema Frac Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.07 kb
#include <bits/stdc++.h>

using namespace std;

ifstream f("frac.in");
ofstream g("frac.out");

const int NMAX=3e5;

int main()
{
    long long n,p;
    f>>n>>p;
    long long v[NMAX+1];
    v[1]=1;
    long long nr=1;
    long long d=2;
    while(d*d<=n)
    {
        if(n%d==0)
        {
            while(n%d==0)
            {
                n/=d;
            }
            for(long long i=1;i<=nr;i++)
            {
                v[i+nr]=-d*v[i];
            }
            nr*=2;
        }
        d++;
    }
    if(n>1)
    {
        for(long long i=1;i<=nr;i++)
        {
            v[i+nr]=-n*v[i];
        }
        nr*=2;
    }
    long long st=1;
    long long dr=LLONG_MAX/4;
    long long sol;
    while(st<=dr)
    {
        long long m=(st+dr)/2;
        long long s=0;
        for(long long i=1;i<=nr;i++)
        {
            s+=m/v[i];
        }
        if(s>=p)
        {
            sol=m;
            dr=m-1;
        }
        else
        {
            st=m+1;
        }
    }
    g<<sol;
    return 0;
}