65. Valid Number (正则表达式)

[LLancelot]

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.

代码

class Solution:
    def isNumber(self, s: str) -> bool:
        return re.match(r'^\s*[+|\-]?(\.\d+|\d+(\.\d*)?)(e[\+|\-]?\d+)?\s*$', s)