Cod sursa(job #228103)
Utilizator | Data | 6 decembrie 2008 14:33:03 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.39 kb |
#include<stdio.h>
#define nmax 2000010
int a[nmax];
int main()
{
long n,x=0;
FILE *f=fopen("ciur.in","r");
FILE *g=fopen("ciur.out","w");
fscanf(f,"%ld",&n);
for(long i=2;i<=n;++i)
if (a[i]==0)
{
for(long j=2*i;j<=n;j+=i) a[j]=1;
x++;
}
fprintf(g,"%ld\n",x);
return 0;
}