Cod sursa(job #744517)
Utilizator | Cazacu Robert taigi100 | Data | 8 mai 2012 21:27:31 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.38 kb |
#include <stdio.h>
using namespace std;
int cont=1;
bool v[2000005];
int main ()
{
freopen ( "ciur.in", "r", stdin);
freopen ( "ciur.out", "w", stdout);
int n;
scanf( "%d", &n);
int i,j;
for ( i=2 ; i<=n ; i*=2)
v[i]=1;
i=3;
while( i <= n)
{
cont++;
for( j=1; j*i<=n; j++)
v[j*i]=1;
while(v[i]==1)
i+=2;
}
printf( "%d", cont);
}