Cod sursa(job #889386)
Utilizator | Data | 24 februarie 2013 14:31:19 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include<fstream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int n, nr, i, j;
int v[2000001];
int main() {
fin >> n;
for (i = 2; i <= n; i++) {
if (v[i] == 0) {
nr++;
for (j = i + i; j <= n; j = j + i)
v[j] = 1;
}
}
fout << nr;
}