Valid Number

Problem

Given a string s, determine if it is a valid numeric value. The string can contain integers, decimals, and/or scientific notation (e.g., "10e5"). Consider valid numbers to include integers, floating-point numbers, and numbers in scientific notation.

Examples:

isValidNumber("0.1")
// returns true

isValidNumber("abc")
// returns false

isValidNumber("-90e3")
// returns true