Cod sursa(job #2951781)

Utilizator AlexSerban21Serban Alexandru AlexSerban21 Data 7 decembrie 2022 12:04:25
Problema Frac Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.71 kb
#include <fstream>
using namespace std;
ifstream fin ("frac.in");
ofstream fout ("frac.out");
long long x,i,j,nr,sol,p,k,d,a,st,mij,dr,b,s,pr;
long long n,v[80005],l[80005],di[80005],nrc;
bool ciur[1000005];
bool f (long long a)
{
    s=0;
    for (i=1; i<=nr+1; i++)
        l[i]=0;
    while (l[nr+1]==0)
    {
        nrc=0;
        pr=1;
        for (i=1; i<=nr+1; i++)
        {
            if (l[i]==1)
                l[i]=0;
            else
            {
                l[i]=1;
                break;
            }
        }
        if (l[nr+1]==0)
        {
            for (i=1; i<=nr; i++)
            {
                if (l[i]==1)
                {
                    pr=pr*di[i];
                    nrc++;
                }
            }
            if (nrc%2==0)
                s=s-a/pr;
            else
                s=s+a/pr;
        }
    }
    sol=a-s;
    if (sol>=p)
        return 1;
    else
        return 0;
}
int main()
{
    ciur[1]=1;
    for (i=2; i<=1000000; i++)
    {
        if (ciur[i]==0)
        {
            v[++k]=i;
            if (i<=10000)
            {
                for (j=i*i; j<=1000000; j=j+i)
                    ciur[j]=1;
            }
        }
    }
    fin>>n>>p;
    s=0;
    x=n;
    nr=0;
    for (d=1; d<=k&&v[d]*v[d]<=x; d++)
    {
        if (x%v[d]==0)
        {
            di[++nr]=v[d];
            while (x%v[d]==0)
                x=x/v[d];
        }
    }
    if (x!=1)
        di[++nr]=x;
    st=1;
    dr=(1ll<<61);
    while (st<=dr)
    {
        mij=(st+dr)/2;
        if (f (mij))
            dr=mij-1;
        else
            st=mij+1;
    }
    fout<<st;
    return 0;
}