#include <stdio.h>

/* the n-th fibonacci number.
 */
unsigned int fib(unsigned int n) {
  unsigned int a = 1, b = 1;
  unsigned int tmp;
  while (--n >= 0) {
    tmp = a;
    a += b;
    b = tmp;
  }
  return a;
}

main() {
  printf("%u", fib(10));
}