Cod sursa(job #2093687)

Utilizator TheNextGenerationAyy LMAO TheNextGeneration Data 24 decembrie 2017 12:57:11
Problema GFact Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.39 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream in("gfact.in");
ofstream out("gfact.out");
int fact[200],put[200],n,q;
long long zero(long long n,long long m)
{
    long long nr=0;
    while(n>=m)
        nr+=(n/=m);
    return nr;
}
bool check(long long nr)
{
    for(int i=0;i<n;i++)
        if(zero(nr,fact[i])<put[i]*q)
            return 0;
    return 1;
}
int main()
{
    long long p,i,r=0,pas=1LL<<60;
    in>>p>>q;
    if(p%2==0)
    {
        fact[0]=2;
        while(p%2==0)
        {
            p/=2;
            put[0]++;
        }
        n=1;
    }
    if(p%3==0)
    {
        fact[n]=3;
        while(p%3==0)
        {
            p/=3;
            put[n]++;
        }
        n++;
    }
    for(i=5;p>1&&i*i<=p;i+=6)
    {
        if(p%i==0)
        {
            fact[n]=i;
            while(p%i==0)
            {
                p/=i;
                put[n]++;
            }
            n++;
        }
        if(p%(i+2)==0)
        {
            fact[n]=i+2;
            while(p%(i+2)==0)
            {
                p/=i+2;
                put[n]++;
            }
            n++;
        }
    }
    if(p>1)
    {
        fact[n]=p;
        put[n]=1;
        n++;
    }
    while(pas)
    {
        if(!check(r+pas))
            r+=pas;
        pas>>=1;
    }
    out<<r+1;
    return 0;
}