Cod sursa(job #2871878)

Utilizator TraianQTraianQ TraianQ Data 15 martie 2022 21:17:11
Problema Frac Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.3 kb
#include <fstream>
#include <bitset>

using namespace std;

long long D[60],sir[1000000];
bitset <10000005> ciur;
long long n,p,st=1,dr=1000000000000000000LL,retin;
long long d=2,ok=0,cnt=0,cn;
long long raspuns(long long a,long long b)
{
        long long rez=0;
        for(int i=0;i<(1<<cnt);i++)
        {
            long long p=1,nr=0;
            for(int j=0;j<cnt;j++)
            {
                if(i&(1<<j))
                {
                    nr++;
                    p*=D[j];
                }
            }
            if(nr%2==0)
                rez+=a/p;
            else
                rez-=a/p;
        }
     return rez;
}

int main()
{
    int cate=0;
    ifstream cin("frac.in");
    ofstream cout("frac.out");
    cin>>n>>p;
    cn=n;
        while(d*d<=cn)
        {
            while(cn%d==0)
            {
                cn/=d;
                ok=1;
            }
            if(ok==1)
                D[cnt++]=d;
            ok=0;
            d++;
        }
        if(cn>1)
            D[cnt++]=cn;
    while(st<=dr)
    {
        long long mij=(st+dr)/2;
        if(raspuns(mij,n) >= p)
        {
            retin = mij;
            dr=mij-1;
        }
        else
            st=mij+1;
    }
    cout<<retin;
    return 0;
}