7-valid-number.md

Valid Number

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.

JavaScript

/**
 * @param {string} s
 * @return {boolean}
 */
var isNumber = function(s) {
        return s.trim().length === 0 ? false : !isNaN(+s);

};

PHP

<?php
        //Enter your code here, enjoy!

var_dump(is_numeric(trim("0")));
var_dump(is_numeric(trim(" 0.1 ")));
var_dump(is_numeric(trim("abc")));
var_dump(is_numeric(trim("1 a")));
var_dump(is_numeric(trim("2e10")));