#include <stdio.h>
#include <dos.h>

static char* numeric[] = { "1", "2", "4", "8", "16", "33", "66", "100" };

void show() {
  unsigned short reg, i;
  outportb(0x22,0x80);
  reg = inportb(0x23);
  i = reg >> 5;
  if ( i > 5 ) i += reg & 1;
  puts(numeric[i]);
}

void setclk(int hyper, int speed) {
  unsigned short reg;
  outportb(0x22,0x80);
  reg = inportb(0x23);
  outportb(0x22,0x80);
  outportb(0x23,(reg & 0xFE) | hyper);
  outportb(0x22,0x40);
  reg = inportb(0x23);
  outportb(0x22,0x40);
  outportb(0x23,(reg & 0xF8) | speed);
}

void main(int argc, char **argv) {
  if (argc == 2) {
    switch (argv[1][0]) {
      case '3': setclk(0,0); break;
      case '6': setclk(0,1); break;
      case '9':
      case '1': setclk(1,1); break;
    }
  }
  sleep(1);
  show();
}