/* sieve.c - It prompts the user to enter an integer N. It prints out
* It prints out all the primes up to N included.
* It uses a sieve method. As primes are found they are
* stored in an array PRIMES and used as possible factors
* for the next potential prime.
*/
#include
#define NPRIMES 1000
#define FALSE 0
#define TRUE 1
int main(void) {
int n;
int i,j;
int flag;
int primes[NPRIMES]; /*It will contain the primes smaller than n
*that we have already encountered*/
int level; /*1+Number of primes currently in PRIMES*/
/*Introduction*/
printf("Enter value of N > ");
scanf("%d",&n);
level = 0;
/*Main body*/
for(i=2;i<=n;i++) {
for(j = 0, flag = TRUE; j