Cod sursa(job #581406)

Utilizator informatician28Andrei Dinu informatician28 Data 14 aprilie 2011 09:13:35
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.29 kb
Raporteaza aceasta sursa 
#include<fstream> 
using namespace std; 
ifstream f("ciur.in");
ofstream g("ciur.out");
int main()
{int nr,suma=0,i,j;
char prim[2000000];
f>>nr;
for(i=2;i<=nr;i++)
	prim[i]=1;
for(i=2;i<=nr;i++)
	if(prim[i])
		{suma++;
			for(j=i*i;j<=nr;j+=i)
			prim[j]=0; 
	}
g<<suma;
}