PAT 甲级 1060 Are They Equal (25 分)(科学计数法,接连做了2天,考虑要全面,坑点多,真麻烦)...

1060 Are They Equal (25 分)

If a machine can save only 3 significant digits, the float numbers 12300 and 12358.9 are considered equal since they are both saved as 0 with simple chopping. Now given the number of significant digits on a machine and two float numbers, you are supposed to tell if they are treated equal in that machine.

Each input file contains one test case which gives three numbers N, A and B, where N (<) is the number of significant digits, and A and B are the two float numbers to be compared. Each float number is non-negative, no greater than 1, and that its total digit number is less than 100.

For each test case, print in a line <code>YES</code> if the two numbers are treated equal, and then the number in the standard form <code>0.d[1]...d[N]*10^k</code> (<code>d[1]</code>&gt;0 unless the number is 0); or <code>NO</code> if they are not treated equal, and then the two numbers in their standard form. All the terms must be separated by a space, with no extra space at the end of a line.

Note: Simple chopping is assumed without rounding.

题意：

给出两个数，问：将他们写成保留N (&lt;100)位小数的科学计数法 <code>0.d[1]...d[N]*10^k</code> (<code>d[1]</code>&gt;0 unless the number is 0); 后，是否相同。若相等，输出YES，并转换结果； 如果不相等，输出NO，并给出两个数的转换结果。

题解:

本题的思路难想而且情况判断非常复杂。

题目要求科学计数法时，两个数是否相等。因此只要判断科学技术法时的本体部分以及指数部分是否相等即可。

对于数据来说，要分为大于 1 与小于 1 来判断，要考虑各种情况下的数字，比如：0000， 000.00， 00123.4， 0.012, 0.00 等

一开始没有考虑太多的异常情况，拿了19分，第二天看了题解的注意点重做，还是只有21分，

第三天理了理思路，其实，只要关注，格式化好后的小数点要点在哪里，次数是多少就可以了，在此基础上，特判0，去掉前导零。比较的时候注意不要超限，输出不够0补齐。

自己编的测试样例：

AC代码：