Cod sursa(job #275485)
| Utilizator |  Nicoara Ionut Ionut_info |
Data | 10 martie 2009 15:02:09 |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 0 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.32 kb |
#include<stdio.h>
long int n,i,j,nr;
FILE *in=fopen("ciur.in","r");
FILE *out=fopen("ciur.in","w");
int main()
{
char p[2000001];
fscanf(in,"%ld",&n);
for(i=1;i<=n;i++) p[i]=0;
for(i=2;i<=n;i++)
{
if(p[i]==0)
{
nr++;
for(j=i*i;j<=n;j+=i)
{
p[j]=1;
}
}
}
fprintf(out,"%ld",nr);
return 0;
}