Cod sursa(job #2668124)
Utilizator | Data | 4 noiembrie 2020 15:22:00 | |
---|---|---|---|
Problema | Fractii | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva de probleme | Marime | 0.44 kb |
#include <bits/stdc++.h>
using namespace std;
int T,n;
vector <int> Ciur(1000005);
int main()
{
ifstream f("fractii.in");
ofstream g("fractii.out");
f>>T;
for(int i=2; i<=1000000; i++)
Ciur[i]=i-1;
for(int i=1; i<=1000000; i++)
for(int j=2*i; j<=1000000; j+=i)
Ciur[j]-=Ciur[i];
int64_t S=0;
for(int i=2; i<=T; i++)
S+=Ciur[i];
g<<(S<<1)+1;
return 0;
}