Valid Number

Please Note:

Note: It is intended for some problems to be ambiguous. You should gather all requirements up front before implementing one.

Please think of all the corner cases and clarifications yourself.

Validate if a given string is numeric.


  • "0" => true
  • " 0.1 " => true
  • "abc" => false
  • "1 a" => false
  • "2e10" => true

Return 0 / 1 ( 0 for false, 1 for true ) for this problem

Clarify the question using “See Expected Output”

  • Is 1u ( which may be a representation for unsigned integers valid?
    For this problem, no.

  • Is 0.1e10 valid?

  • -01.1e-10?

  • Hexadecimal numbers like 0xFF?
    Not for the purpose of this problem

  • 3. (. not followed by a digit)?

  • Can exponent have decimal numbers? 3e0.1?
    Not for this problem.

  • Is 1f ( floating point number with f as prefix ) valid?
    Not for this problem.

  • How about 1000LL or 1000L ( C++ representation for long and long long numbers )?
    Not for this problem.

  • How about integers preceded by 00 or 0? like 008?
    Yes for this problem

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