Cod sursa(job #2378365)
Utilizator | bcosmin bcosmin | Data | 12 martie 2019 09:03:20 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.43 kb |
#include <bits/stdc++.h>
using namespace std;
bitset <2000002> w; // SAU bool w[2000002];
int i, j, n, cnt;
int main()
{
ifstream f("ciur.in");
ofstream g("ciur.out");
f >> n;
for(i = 2; i <= n; i ++)
if(w[i] == false)
{
cnt ++;
for(j = i + i; j <= n; j = j + i)
w[j] = true;
}
g << cnt;
f.close();
g.close();
return 0;
}