Cod sursa(job #2909793)
Utilizator | Data | 15 iunie 2022 20:36:50 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include <bits/stdc++.h>
#define N 2000005
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int main()
{
int n, ciur[N]={0}, cnt=0;
fin>>n;
for(int i=2; i<=n; i++)
if(ciur[i]==0)
{
++cnt;
for(int j=i*2; j<=n+1; j=j+i)
ciur[j]=1;
}
fout<<cnt;
return 0;
}