Validate if a given string is numeric.

Some examples:

"0" => true

" 0.1 " => true

"abc" => false

"1 a" => false

"2e10" => true

Note: It is intended for the problem statement to be ambiguous. You should gather all requirements up front before implementing one.

Notice that "3." is a valid number, so the regular expression between two brackets should be \\d*.

 

public class Solution {    public boolean isNumber(String s) {        return s.trim().matches("[-+]?(\\d+\\.?|\\.\\d+)\\d*([eE][-+]?\\d+)?");    }}