Cod sursa(job #2452016)

Utilizator calexnicolescuNicolescu Alexandru calexnicolescu Data 29 august 2019 08:58:24
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.29 kb
Raporteaza aceasta sursa 
#include <iostream>
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int n,p,i,j,s;
bool x[2000032];
int main()
{f>>n;
for(i=2;i*i<=n;i++)
    if(x[i]==0)
    for(j=i*2;j<=n;j+=i)x[j]=1;
for(i=2;i<=n;i++)if(x[i]==0)s++;
g<<s;

    return 0;
}