Cod sursa(job #2253597)

Utilizator whitewolf3131Ursu Laurentiu Cristian whitewolf3131 Data 4 octombrie 2018 10:25:33
Problema Fractii Scor 10
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.58 kb
#include <fstream>
#include <string>

using namespace std;

ifstream in("fractii.in");
ofstream out("fractii.out");

bool cmmdc(int a, int b){
    int c;
    while(b){
        c=a%b;
        a=b;
        b=c;
    }
    if(a==1){
        return false;    
    }
    return true;
}
int main()
{
    int n;
    in>>n;
    long long tot=n*n;
    long long totneg=0;
    for(int i=2; i<=n; i++){
        for(int j=2; j<i; j++){
            if(cmmdc(i, j)){
                totneg+=2;
            }    
        }         
    }
    totneg+=n-1;
    out<<tot-totneg;
}