primesieve  7.3
prev_prime.c

Iterate backwards over primes using primesieve_iterator.

#include <primesieve.h>
#include <inttypes.h>
#include <stdio.h>
int main()
{
/* primesieve_skipto(&it, start_number, stop_hint) */
primesieve_skipto(&it, 2000, 1000);
uint64_t prime;
/* iterate over primes from 2000 to 1000 */
while ((prime = primesieve_prev_prime(&it)) >= 1000)
printf("%" PRIu64 "\n", prime);
return 0;
}