Reverse digits of a number / Palindromic Number or not

Write an optimal C program to reverse digits of a number.Also check whether the number is palindromic or NOT

Iterative Way:
//4562 ->2654
int reversDigits(int num)
{
int rev_num = 0;
while(num > 0)
{
rev_num = rev_num*10 + num%10;
num = num/10;
}
return rev_num;
}

Time Complexity: O(Log(n)) where n is the input number.

Recursive way:-
int reversDigits(int num)
{
static int rev_num = 0;
static int base_pos = 1;
if(num > 0)
{
reversDigits(num/10);
rev_num += (num%10)*base_pos;
base_pos *= 10;
}
return rev_num;
}

Time Complexity: O(Log(n)) where n is the input number
Note that above above program doesn’t consider leading zeroes. For example, for 100 program will print 1.

For printing Trailing Zeros:-------------

#include<stdio.h>

 

void reversDigits(unsigned int num)

{

  int rev_num = 0,zeros=0;

  while(num >0)

  {

    /*count trailing zeroes,

     i.e., for 100 zeros will be 2*/       

    if(num%10==0)

    {  

      zeros++;

      num = num/10;

    }

    else break;

  }

 

  /* Get the reverse number */

  while(num > 0)

  {

    rev_num = rev_num*10 + num%10 ;

    num = num/10;

  }

   

  /* print leading zeroes in reverse number */

  while(zeros--)

    printf("0");

 

  /* print reverse number */

  printf("%d\n",rev_num);

}

 

int main()

{

  unsigned int x = 100;

  reversDigits(x);

  getchar();

}