Cod sursa(job #1402031)
Utilizator | Data | 26 martie 2015 11:50:26 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | c | Status | done |
Runda | Arhiva educationala | Marime | 0.49 kb |
#include <stdio.h>
char ciur[2000001];
int main()
{
FILE *fin, *fout;
int n, prime, div, j;
fin = fopen ( "ciur.in", "r" );
fout = fopen ( "ciur.out", "w" );
fscanf ( fin, "%d", &n );
fclose ( fin );
prime = 0;
for ( div = 2; div < n; div++ ) {
if ( ciur[div] == 0 ) {
prime++;
for ( j = div + div; j <= n; j = j + div ) {
ciur[j] = 1;
}
}
}
fprintf( fout, "%d", prime );
fclose ( fout );
return 0;
}