Cod sursa(job #1854753)

Utilizator amaliarebAmalia Rebegea amaliareb Data 23 ianuarie 2017 11:00:20
Problema Factorial Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.48 kb
#include <iostream>
#include <fstream>

using namespace std;
ifstream f("fact.in");
ofstream g("fact.out");
unsigned long long p,n,i,pas,L=32,r;

long long nr5(long long n)
{
    long long nr=0;
    while(n)
    {
        nr+=n/5;
        n/=5;
    }
    return nr;
}

int main()
{
    f>>p;
    L=32;
    pas=1LL<<L;
    cout<<pas<<'\n';
    r=0;
    while(pas)
    {
        if(nr5(r+pas)<p) r+=pas;
        pas/=2;
    }
    if(nr5(r+1)==p) g<<r+1<<'\n';
    else g<<-1<<'\n';
    return 0;
}