ValidNumber.py

"""
Validate if a given string can be interpreted as a decimal number.

Some examples:
"0" => true
" 0.1 " => true
"abc" => false
"1 a" => false
"2e10" => true
" -90e3   " => true
" 1e" => false
"e3" => false
" 6e-1" => true
" 99e2.5 " => false
"53.5e93" => true
" --6 " => false
"-+3" => false
"95a54e53" => false

Note: It is intended for the problem statement to be ambiguous. You should gather all requirements up front before implementing one. However, here is a list of characters that can be in a valid decimal number:

Numbers 0-9
Exponent - "e"
Positive/negative sign - "+"/"-"
Decimal point - "."
Of course, the context of these characters also matters in the input.

Update (2015-02-10):
The signature of the C++ function had been updated. If you still see your function signature accepts a const char * argument, please click the reload button to reset your code definition.

判断可否化为数字。
虽然使用float是作弊行为，但还是忍不住用了...
当做零启动任务吧。
测试地址：
https://leetcode.com/problems/valid-number/description/

"""

class Solution(object):
    def isNumber(self, s):
        """
        :type s: str
        :rtype: bool
        """
        try:
            float(s)
            return True
        except:
            return False