Task
Given a string, output its longest prefix which contains only digits.
A substring of a string is called a prefix if it starts at the string’s first character.
Example
For inputString = "123aa1", the output should be
longestDigitsPrefix(inputString) = "123".
Input/Output
-
[execution time limit]
4 seconds (py3) -
[input] string inputString
Guaranteed constraints:3 ≤ inputString.length ≤ 100. -
[output] string
My Solution
def longestDigitsPrefix(inputString):
if not inputString[0].isdigit():
return ""
for i in range(len(inputString)):
if not inputString[i].isdigit():
return inputString[:i]
return inputString