//test clock.c on ccbsd2.cs.nctu.edu.tw  (FreeBSD 6.3-RELEASE-p4 )
/********
CLK_TCK=128.000000
CLOCKS_PER_SEC=128.000000
About to compute Fibonacci number..
 You can TRY n=19,35,36,37,38,45,46,49, 90,91,92
fib is a recursive version, fib22 uses LOOP.
Enter 3838 for calling fib22, or I will call fib:

fib(19)= 6765
Time used: 0 ticks === 0.000000 seconds.

fib(20)= 10946
Time used: 0 ticks === 0.000000 seconds.


fib(35)= 14930352
Time used: 28 ticks === 0.218750 seconds.

fib(36)= 24157817
Time used: 46 ticks === 0.359375 seconds.

fib(37)= 39088169
Time used: 74 ticks === 0.578125 seconds.

fib(38)= 63245986
Time used: 120 ticks === 0.937500 seconds.

fib(39)= 102334155
Time used: 193 ticks === 1.507812 seconds.

fib(40)= 165580141
Time used: 315 ticks === 2.460938 seconds.

fib(41)= 267914296
Time used: 510 ticks === 3.984375 seconds.

fib(42)= 433494437
Time used: 824 ticks === 6.437500 seconds.

fib(43)= 701408733
Time used: 1335 ticks === 10.429688 seconds.

fib22(44)= 1134903170
fib22(45)= 1836311903
fib22(46)= 2971215073
fib22(47)= 4807526976
fib22(48)= 7778742049
fib22(49)= 12586269025
fib22(50)= 20365011074
fib22(51)= 32951280099
fib22(52)= 53316291173

fib22(90)= 4660046610375530309
fib22(91)= 7540113804746346429
fib22(92)= -6246583658587674878   /// overflow long long 

預估:
   44:  17 秒
   45:  27 秒
   46:  44 秒
   47:  71 秒
   48:  2分
   49:  3分
   50:  5分
   51:  8分
   52:  13分鐘
****************/