Cod sursa(job #2874777)

Utilizator darisavuSavu Daria darisavu Data 20 martie 2022 11:12:43
Problema Frac Scor 0
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.44 kb
#include <bits/stdc++.h>
#define ll long long
#define mx 1000001
using namespace std;
ifstream f("frac.in");
ofstream g("frac.out");
ll a[25],sol[25],prim[100005];
bool ciur[1000005];
ll A,B,t,k,sum,nrp;
ll st,dr,mij,x,y,sol2;
void desc(ll nr)
{
    int j=1;
    k=0;
    memset(a,0,sizeof(a));
    while(prim[j]*prim[j]<=nr&&nr>1)
    {
        if(nr%prim[j]==0)
        {
            k++;
            a[k]=prim[j];
            while(nr%prim[j]==0) nr=nr/prim[j];
        }
        j++;
    }
    if(nr>1)
    {
        k++;
        a[k]=nr;
    }
}
void verif(int nr)
{
    ll prod=1;
    for(int i=1; i<=nr; i++)
    {
        prod*=a[sol[i]];
    }
    if(nr%2==0) sum+=A/prod;
    else sum-=A/prod;
}
void submultimi(int n)
{
    int i,j;
    for(i=1; i<(1<<n); i++)
    {
        int p=0;
        for(j=0; j<n; j++)
            if( i & (1<<j)) sol[++p]=j+1;
        verif(p);
    }
}
int main()
{
    int i,j;
    f>>x>>y;
    for(i=2; i<=mx; i++)
    {
        if(!ciur[i])
        {
            prim[++nrp]=i;
            for(j=i+i; j<=mx; j=j+i) ciur[j]=1;

        }
    }
    st=1;
    dr=100000000000000;
    B=x;
    desc(B);
    while(st<=dr)
    {
        mij=(st+dr)/2;
        A=mij;
        sum=A;
        submultimi(k);
        if(sum<y) st=mij+1;
        else if(sum>=y)
        {
            dr=mij-1;
            sol2=A;
        }
    }
   g<<sol2;



    return