WA的滋味

 HOJ 1474

 

How Many Fibs?

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Time limit:	1sec.	Submitted:	198
Memory limit:	32M	Accepted:	65

Source : University of Ulm Internal Contest 2000

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Recall the definition of the Fibonacci numbers:

f1 := 1
f2 := 2
fn := fn-1 + fn-2 (n >= 3)

Given two numbers a and b, calculate how many Fibonacci numbers are in the range [a, b].

Input

The input contains several test cases. Each test case consists of two non-negative integer numbers a and b. Input is terminated by a = b = 0. Otherwise, a <= b <= 10^100. The numbers a and b are given with no superfluous leading zeros.

Output

For each test case output on a single line the number of Fibonacci numbers fi with a <= fi <= b.

Sample Input

10 100
            1234567890 9876543210
            0 0

Sample Output

5
            4

这是个高精度加二分法查找的问题，不能说难，但也不简单（至少以我现在的水平看来）。我写高精度和二分法都很快写好了，但最终导致今天WA了几个小时却是因为我太不成熟，我对自己的代码也只是有个大概的印象，而不是精确的把握。遇到要分析细节的时候脑子不够冷静。

今天我算是尝透了WA的滋味，我拿着正确的程序，自己想各种各样变态的输入然后对比输出，发现差异后扎进代码里找BUG，好不容易改得和正确输出一样了，战战兢兢地交一遍，然后是无言的但沉重得像一座大山的Wrong Answer！捶过桌子之后抬起头还得再改。。。。。。

奋战了这么久，不过总算是AC了，但可笑的是我还得在心里大呼“Thank God!”，上天垂怜！.AC之后还得熬夜在这儿写着。。。