Cod sursa(job #1791182)

Utilizator nick12nicolae mihalache nick12 Data 29 octombrie 2016 10:27:59
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.3 kb
#include <bits/stdc++.h>

using namespace std;

int main()
{
    int N;
    cin >> N;
    int p{0};
	int i, j, a[N+1];
	for (a[1] = 0, i = 2; i <= N; i++)
		a[i] = 1;
	for (i = 2; i <= N / 2; i++)
		for (j = 2; j <= N / i; j++)
			a[i*j] = 0;
	for (i = 1; i <= N; i++)
		if (a[i]) p++;
	printf("%d",p);
}