Cod sursa(job #2203355)

Utilizator skoda888Alexandru Robert skoda888 Data 11 mai 2018 23:10:01
Problema Fractii Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.33 kb
Raporteaza aceasta sursa 

#include <iostream>
#include <fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int n,i,j,v[1000001];
long long nr;
int main()
{   f>>n;
    for(i=1;i<=n;i++)v[i]=i;
    for(i=1;i<=n;i++)
    {
        nr+=v[i];

        for(j=i+i;j<=n;j+=i)
        v[j]-=v[i];}
    g<<2*nr-1;



}