Cod sursa(job #555040)
Utilizator | Data | 15 martie 2011 11:20:54 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 40 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include <stdio.h>
#define MAX 2000005
bool a[MAX];
int main()
{
int c=0,i,j;
FILE *in=fopen("ciur.in","r"),*out=fopen("ciur.out","w");
int n;
fscanf(in,"%i",&n);
for(i=2;i<=n;i++)
{
if(a[i]==0)
{
c++;
j=i;
while(j<n)
{
j=j+i;
a[j]=1;
}
}
}
fprintf(out,"%i",c);
}