Cod sursa(job #793513)

Utilizator erik95Scharscher Erik erik95 Data 3 octombrie 2012 13:46:09
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.32 kb
Raporteaza aceasta sursa 
#include<iostream>
#include<fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
long n,i,j;
int nr;
unsigned char p[2000000];
int main()
{f>>n;
for(i=2;i<=n;i++)
	p[i]=1;
for(i=2;i<=n;i++)
	if(p[i]==1)
		{nr++;
		for(j=i+i;j<=n;j+=i)
			p[j]=0;
		}
g<<nr;
f.close();
g.close();
}