Problem
A valid number can be split up into these components (in order):
- A decimal number or an integer.
- (Optional) An
'e'
or 'E'
, followed by an integer.
A decimal number can be split up into these components (in order):
- (Optional) A sign character (either
'+'
or '-'
).
- One of the following formats:
- At least one digit, followed by a dot
'.'
.
- At least one digit, followed by a dot
'.'
, followed by at least one digit.
- A dot
'.'
, followed by at least one digit.
An integer can be split up into these components (in order):
- (Optional) A sign character (either
'+'
or '-'
).
- At least one digit.
For example, all the following are valid numbers: ["2", "0089", "-0.1", "+3.14", "4.", "-.9", "2e10", "-90E3", "3e+7", "+6e-1", "53.5e93", "-123.456e789"]
, while the following are not valid numbers: ["abc", "1a", "1e", "e3", "99e2.5", "--6", "-+3", "95a54e53"]
.
Given a string s
, return true
if s
is a valid number.