{ "data": { "question": { "questionId": "65", "questionFrontendId": "65", "boundTopicId": null, "title": "Valid Number", "titleSlug": "valid-number", "content": "

A valid number can be split up into these components (in order):

\n\n
    \n\t
  1. A decimal number or an integer.
    2. \n\t
  2. (Optional) An 'e' or 'E', followed by an integer.
    3. \n
\n\n

A decimal number can be split up into these components (in order):

\n\n
    \n\t
  1. (Optional) A sign character (either '+' or '-').
    2. \n\t
  2. One of the following formats:\n\t
      \n\t\t
    1. One or more digits, followed by a dot '.'.
      2. \n\t\t
    2. One or more digits, followed by a dot '.', followed by one or more digits.
      3. \n\t\t
    3. A dot '.', followed by one or more digits.
      4. \n\t
    \n\t
    3. \n
\n\n

An integer can be split up into these components (in order):

\n\n
    \n\t
  1. (Optional) A sign character (either '+' or '-').
    2. \n\t
  2. One or more digits.
    3. \n
\n\n

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"].

\n\n

Given a string s, return true if s is a valid number.

\n\n

 

\n

Example 1:

\n\n
\nInput: s = "0"\nOutput: true\n
\n\n

Example 2:

\n\n
\nInput: s = "e"\nOutput: false\n
\n\n

Example 3:

\n\n
\nInput: s = "."\nOutput: false\n
\n\n

 

\n

Constraints:

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Most standard library headers are already included automatically for your convenience.

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Python 2.7.12.

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For Map/TreeMap data structure, you may use sortedcontainers library.

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Compiled with gcc 8.2 using the gnu99 standard.

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\\r\\n\\r\\n

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\\r\\n

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C# 10 with .NET 6 runtime

\\r\\n\\r\\n

Your code is compiled with debug flag enabled (/debug).

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Node.js 16.13.2.

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Your code is run with --harmony flag, enabling new ES6 features.

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Ruby 3.1

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