Cod sursa(job #171216)
| Utilizator |  Ghiuta Alex ghiutaalex |
Data | 3 aprilie 2008 21:02:06 |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 0 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.31 kb |
#include<stdio.h>
#define M 2000005
long n,c[M],r;
FILE*f=fopen("ciur.in","r");
FILE*g=fopen("ciur.out","w");
int main()
{long i,j;
fscanf(f,"%ld",&n);
for(i=2;i<=n;i++)
c[i]=1;
for(i=2;i<=n;i++)
{if(c[i]) {r++;
for(j=i;j<=n;j+=i)
c[j]=0;}}
fprintf(g,"%ld",r);
fcloseall();
return 0;
}