Cod sursa(job #3193097)
Utilizator | Szucs Patrik - Kevin PatrikKev75 | Data | 13 ianuarie 2024 23:05:32 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.58 kb |
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
ifstream in("ciur.in");
ofstream out("ciur.out");
int n;
in >> n;
bool prim[n + 1];
for (int i = 2; i * i <= n; i++)
{
if (prim[i] == 0)
{
for (int j = 2 * i; j <= n; j += i)
{
prim[j] = 1;
}
}
}
int ossz = 0;
for (int i = 2; i <= n; i++)
{
if (prim[i] == 0)
{
ossz++;
}
}
out << ossz;
return 0;
}