text: #include <stdio.h>
  #include "mythread.h"
  
  void foo(int c) {
      while (1) {
          printf("foo : %d\n", c);
          c += 1;
          yield();
      }
  }
  
  void bar(int c) {
      while (1) {
          printf("bar : %d\n", c);
          yield();
          c += 2;
      }
  }
  
  void baz(int c) {
      while (1) {
          printf("baz : %d\n", c);
          yield();
          c += 3;
          printf("baz : %d\n", c);
          yield();
          c += 3;
      }
  }
  
  int main() {
      new_thread(foo, 0);
      new_thread(bar, 0);
      new_thread(baz, 0);
      start_threads();
      return 0;
  }
  