Cod sursa(job #2052254)
Utilizator | Pop Nicolae NicuPop | Data | 30 octombrie 2017 12:29:30 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include <iostream>
#include <fstream>
using namespace std;
int a[200000];
int main()
{int n,i,j,k=0;
ifstream f("ciur.in");
ofstream g("ciur.out");
f>>n;
for(i=2;i<=n;i++)
a[i]=1;
for(i=2;i<=n;i++)
if(a[i])
for(j=i+i;j<=n;j+=i)
a[j]=0;
for(i=1;i<=n;i++)
if(a[i]==1)
k++;
g<<k;
}