【LeetCode】65. Valid Number

心已赠人 2022-03-22 10:12 165阅读 0赞

#### introduction ####

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.

#### Solution ####

class Solution(object):
        def isNumber(self, s):
            """ :type s: str :rtype: bool """
            if s.isdigit():
                return True
            elif "e" in s and "." in s and s.split("e") == 2:
                s1, s2 = s.split("e")
                try:
                    return float(s1) and float(s2)
                except ValueError:
                    return False
            else:
                try:
                    float(s)
                    return True
                except ValueError:
                    return False

[https://leetcode.com/submissions/detail/210536753/][https_leetcode.com_submissions_detail_210536753]

#### Code ####

GitHub：[https://github.com/roguesir/LeetCode-Algorithm][https_github.com_roguesir_LeetCode-Algorithm]

*  更新时间：2019-02-25

[https_leetcode.com_submissions_detail_210536753]: https://leetcode.com/submissions/detail/210536753/
[https_github.com_roguesir_LeetCode-Algorithm]: https://github.com/roguesir/LeetCode-Algorithm