Cod sursa(job #904245)
Utilizator | Data | 3 martie 2013 22:56:06 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include <stdio.h>
FILE *f,*s;
int m,n,i,j;
int v[2000000];
int main()
{
f=fopen("ciur.in","r");
s=fopen("ciur.out","w");
fscanf(f,"%d",&n);
m=1;
for(i=3;i<=n;i+=2)
{
if(v[i]==0)
{
m++;
for(j=i+i;j<=n;j+=i)
v[j]=1;
}
}
fprintf(s,"%d",m);
fclose(s);
return 0;
}