Cod sursa(job #526368)
| Utilizator |  catana marina marinutza |
Data | 28 ianuarie 2011 10:25:13 |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 30 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.36 kb |
#include<stdio.h>
#include<math.h>
int n,i,k,nr,a[2000005];
int main()
{
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%d",&n);
a[0]=1;
a[1]=1;
for(i=2;i<sqrt(n);i++)
{
for(k=2;k*i<=n;k++)
{
a[k*i]=1;
}
}
for(i=2;i<=n;i++)
{
if(a[i]==0)
{
nr=nr+1;
}
}
printf("%d",nr);
return 0;
}