# ---
# title: 65. Valid Number
# id: problem65
# author: Tian Jun
# date: 2020-10-31
# difficulty: Hard
# categories: Math, String
# link: <https://leetcode.com/problems/valid-number/description/>
# hidden: true
# ---
# 
# Validate if a given string can be interpreted as a decimal number.
# 
# Some examples:  
# `"0"` => `true`  
# `" 0.1 "` => `true`  
# `"abc"` => `false`  
# `"1 a"` => `false`  
# `"2e10"` => `true`  
# `" -90e3   "` => `true`  
# `" 1e"` => `false`  
# `"e3"` => `false`  
# `" 6e-1"` => `true`  
# `" 99e2.5 "` => `false`  
# `"53.5e93"` => `true`  
# `" --6 "` => `false`  
# `"-+3"` => `false`  
# `"95a54e53"` => `false`
# 
# **Note:** It is intended for the problem statement to be ambiguous. It would
# be best if you gathered all requirements up front before implementing one.
# However, here is a list of characters that can be in a valid decimal number:
# 
#   * Numbers 0-9
#   * Exponent - "e"
#   * Positive/negative sign - "+"/"-"
#   * Decimal point - "."
# 
# Of course, the context of these characters also matters in the input.
# 
# 
# 
# **Example 1:**
# 
#     
#     
#     Input: s = "0"
#     Output: true
#     
# 
# **Example 2:**
# 
#     
#     
#     Input: s = "3"
#     Output: true
#     
# 
# 
# 
# **Constraints:**
# 
#   * `1 <= s.length <= 20`
#   * `s` consists of only English letters, digits, space `' '`, plus `'+'`, minus `'-'`, or dot `'.'`.
# 
# 
## @lc code=start
using LeetCode

## add your code here:
## @lc code=end
