tests/bench_421_ref.c

   1 #include <stdio.h>
   2 int count_421(int n) {
   3         int steps = 0;
   4         while (n > 1) {
   5                 steps++;
   6                 if (n%2==0)
   7                         n /= 2;
   8                 else
   9                         n = n * 3 + 1;
  10         }
  11         return steps;
  12 }
  13
  14 int main(int argc, char ** argv) {
  15         int n = 10;
  16         int i, v;
  17         int max_i, max_v;
  18         if (argc>1) {
  19                 n = atoi(argv[1]);
  20         }
  21
  22         max_i = 1;
  23         max_v = 0;
  24         for(i=2; i<=n; i++) {
  25                 v = count_421(i);
  26                 if (v >= max_v) {
  27                         max_i = i;
  28                         max_v = v;
  29                 }
  30         }
  31
  32         printf("%d: %d\n", max_i, max_v);
  33         return 0;
  34 }