Cod sursa(job #1715835)
Utilizator | Tifui Ioan Alexandru tifui.alexandru | Data | 11 iunie 2016 15:38:07 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.29 kb |
#include <iostream>
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
bool a[2000001];
int main()
{int n,i,j;
f>>n;
int nr=0;
for(i=2;i<=n;i++)
if(a[i]==false)
{
nr++;
for(j=i+i;j<=n;j=j+i)
a[j]=true;
}
g<<nr;
return 0;
}