Cod sursa(job #516911)
Utilizator | Data | 26 decembrie 2010 23:14:00 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include <stdio.h>
int N, c;
char a[2000005];
int main() {
int i, j;
freopen("ciuri.txt", "r", stdin);
freopen("ciur.txt", "w", stdout);
scanf("%d", &N);
for(i=2; i<=N; i++)
if (!a[i]) {
++c;
for (j = i+i; j<=N; j+=i)
a[j]=1;
}
printf("%d\n", c);
return 0;
}