Cod sursa(job #2212660)
Utilizator | Data | 14 iunie 2018 15:58:17 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 60 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include <iostream>
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int n,j,k=0,prim[2000001],i;
int main()
{
f>>n;
for(i=2;i<=n;i++)
prim[i]=1;
for(i=1;i<=n;i++)
if(prim[i])
{
k++;
for(j=i+i;j<=n;j+=i)
prim[j]=0;
}
g<<k;
}