Power of Two

[shubhankar-99]

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shubhankarrr

Category of the bug :

Question

Description of the bug :

The questions statement is not clear

Code you used for Submit/Run operation :

#include <math.h>

class Solution {
  public:
    bool isPalindrome(int x) {
      // negative numbers arne't symmetric
      if (x < 0) return false;

      /*
      * 10^b = x ... what is b? That is what log base 10 asks.
      * 
      * 'logarithmAnswer' is b.
      */
      double logarithmAnswer = log10(x);

      /*
      * 'logarithmAnswer' can be a float value. Like:
      * 
      * log10(99) ≈ 1.99564 (meaning that 10^1.99564 ≈ 99)
      * 
      * So to get rid of the decimal part we floor it & then add 1
      */
      int totalDigits = ((int) floor(logarithmAnswer)) + 1;

       /*
      * If x = 999, we have 3 digits, so we want a mask the length of the integer.
      * 
      * 100 = 10^2, so 10^(digits - 1), we will use this later to extract & remove
      * the most significant digit
      */
      int mostSignificantExtractionMask = (int) pow(10, totalDigits - 1);

      // Iterate half the total amount of digits, check both ends
      for (int i = 0; i < (totalDigits / 2); i++) {
        int mostSignificantDigit = x / mostSignificantExtractionMask;
        int onesPlaceDigit = x % 10;

        if (mostSignificantDigit != onesPlaceDigit) {
          return false;
        }

        // Removing most significant digit: 999 % 100 = 99
        x %= mostSignificantExtractionMask;

        /*
        * Removing the ones place digit: 99 / 10 = 9.9 => 9 (.9 truncated since this is
        * not a float type, it is an integer)
        */
        x /= 10;

        // Remove 2 0's from the mask since we just lost 2 digits
        mostSignificantExtractionMask /= 100;
      }

      return true;
    };
};

Language used for code :

Expected behavior :

It should be 2 instead of true

Screenshots :

Additional context :

Please do it fast

[shubhankar-99]

Thank you , Your issue is resolved.