Cod sursa(job #383691)
Utilizator | Data | 17 ianuarie 2010 18:02:19 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.29 kb |
#include <cstdio>
char v[2000001];
int main(){
int n;
freopen("ciur.in","rt",stdin);
freopen("ciur.out","wt",stdout);
scanf("%d",&n);
int i,j;
int ct=0;
for(i=0;i<n;i++)
v[i]=1;
for(i=2;i<n;i++)
if(v[i]){
ct++;
for(j=2;j<n/i;j++)
v[i*j]=0;
}
printf("%d",ct);
}