/* On p.44 of Dasgupta, Papadimitriou, and Vazirani, they ugh about how “very
 * slow” it would be to use sequential search over a list of 250 IP
 * addresses, one page after they’re breezing over how RSA is
 * “simple”, “convenient”, and “elementary”.  This program shows that
 * sequential searching over an array of 250 IP addresses takes about
 * 0.45μs on my netbook.  RSA-2048, by contrast, is about
 * 110000μs to sign and 1500μs to verify on the same machine,
 * according to `openssl speed rsa`.
 */

#include <stdint.h>
#include <stdlib.h>

enum { n_ips = 250 };

int main(int argc, char **argv) {
  int ips[n_ips];
  int matches = 0;

  srandom(37);
  for (int i = 0; i < n_ips; i++) {
    ips[i] = random();
  }
  for (int i = 0; i < 10000; i++) {
    for (int j = 0; j < n_ips; j++) {
      for (int k = 0; k < n_ips; k++) {
        if (ips[j] == ips[k]) {
          matches++;
          break;
        }
      }
    }
  }
  return matches;
}