Cod sursa(job #1947062)
Utilizator | Data | 30 martie 2017 18:24:40 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include<bits/stdc++.h>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
long long n,sol;
bitset<2000005>v;
int main()
{
v[0]=1;
v[1]=1;
f>>n;
for(int i=2;i<=n;++i)
if(!v[i])
{
sol++;
for(int j=i+i;j<=n;j+=i)
v[j]=1;
}
g<<sol;
}