Cod sursa(job #2056424)

Utilizator LucaSeriSeritan Luca LucaSeri Data 4 noiembrie 2017 11:41:01
Problema Principiul includerii si excluderii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.21 kb
#include <bits/stdc++.h>

using namespace std;

vector<int> ciur;
bool viz[1000010];

ifstream f("pinex.in");
ofstream g("pinex.out");

void ciurulet(){
    for(int i = 2; i < 1000010; ++i){
        if(!viz[i]){
            ciur.push_back(i);
            for(int j = i; j < 1000010; j += i) viz[j] = true;
        }
    }
}

void solve(long long a, long long b){
    int divizori[50];
    int nr = 0;
    for(int i = 0;  i < ciur.size() && ciur[i]*ciur[i] <= b; ++i){
        if(b % ciur[i]) continue;
        divizori[++nr] = ciur[i];
        while(b % ciur[i] == 0) b /= ciur[i];
    }

    if(b != 1) divizori[++nr] = b;

    long long sol = a;
    for(int mask = 1; mask < (1<<nr); ++mask){
        long long cnt = 0, prod = 1;
        for(int j = 0; j < nr; ++j){
            if((1<<j)&mask){
                ++ cnt;
                prod = 1LL * prod * divizori[j+1];
            }
        }
        if(cnt % 2) cnt = -1;
        else cnt = 1;

        sol = sol + 1LL*cnt*(a/prod);

    }

    g << sol << '\n';
}
int main(){
    int T;
    f >> T;
    ciurulet();
    while(T --){
        long long a, b;
        f >> a >> b;
        solve(a, b);
    }

    return 0;
}