48 - ZOJ Monthly, November 2005 - 1008
Given a string, you should validate whether the string represents a legal float number. The legal float number should in this pattern: ^([\+\-])?(?<integral_digits>\d*)?((\.)(?<fractional_digits>\d*))?(([eE])(?<exponent>[\+\-]?\d+))?$ Obviously if both fractional_digits and integral_digits part are empty, this string is also illegal.
There are multiple test cases, each with a string in a line(no extra blanks in this string). The test cases end with a single '#' in a line.
If the string represents a legal float number, output 'Yes' in a line. Otherwise output 'No'.
1.1e11 1.1e1.1 #
Author: HUANG, Ninghai