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# Valid Number InterviewBit Solution

Problem: Valid Number

### Problem Description:

Validate if a given string is numeric.

Examples:

• "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? Yes

• -01.1e-10? Yes

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

• 3. (. not followed by a digit)? No

• 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

## Solution Approach

First, try to find if it has any character other than digits or not.

If it doesn't have any character other than a digit, you can return true.

If it has some characters in it, try to check whether it denotes a sign, exponent or decimal. If yes then you are good to go return true, otherwise false.

In C++

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