Cod sursa(job #637450)
| Utilizator |  Diaconu Ion johnny2008 |
Data | 20 noiembrie 2011 14:31:20 |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 100 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.34 kb |
#include<fstream>
#include<iostream>
#include <string>
using namespace std;
bool lol[2000001];
int main(){
ifstream f("ciur.in");
ofstream g("ciur.out");
int n;
f>>n;
long long i,ct=0,j;
for(i=2;i<=n;++i)
{
if(lol[i]!=true){
++ct;
for(j=i;j*i<=n;++j)
{
lol[i*j]=true;
}
}
}
g<<ct;
return 0;
}