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. Example 1: Input: s = "0" Output: true Example 2: Input: s = "e" Output: false Example 3: Input: s = "." Output: false Example 4: Input: s = ".1" Output: true Constraints: 1 <= s.length <= 20 s consists of only English letters (both uppercase and lowercase), digits (0-9), plus '+', minus '-', or dot '.'.