Cod sursa(job #2019114)

Utilizator vladm98Munteanu Vlad vladm98 Data 6 septembrie 2017 23:11:05
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
#include <bits/stdc++.h>

using namespace std;
bitset <2000004> fv;
int main(int argc, char const *argv[])
{
	ifstream fin ("ciur.in");
	ofstream fout ("ciur.out");
	int n;
	fin >> n;
	int ans = 0;
	for (int i = 2; i<=n; ++i)
		if (fv[i] == 0)
		{
			++ans;
			for (int j = i+i; j<=n; j+=i)
				fv[j] = 1;
		}
	fout << ans;
	return 0;
}