CareerCup

def step_num_count(n, m, num):
	count  = 0
	q = []
	q.append(num)
	while q:
		step_num = q.pop(0)
		if step_num >= n and step_num <= m and (step_num/10):
			count += 1
		if step_num  is 0 or step_num > m:
			continue
		last_digit = step_num % 10
		step_num1 = (step_num * 10) + last_digit + 1
		step_num2 = (step_num * 10) + last_digit - 1
		if last_digit is 0:
			q.append(step_num1)
		elif last_digit is 9:
			q.append(step_num2)
		else:
			q.append(step_num1)
			q.append(step_num2)
	return count		
			
def main():
	count = 0
	n = 0
	m = 21
	for i in range(10):
		count += step_num_count(n, m, i)
	print "Total stepping num :",count
	
main()

Missed out few points from qn. Corrected in this upload

def step_num_count(n1, n2, num):
	count  = 0
	q = []
	q.append(num)
	while q:
		step_num = q.pop(0)
		if step_num >= n1 and step_num <= n2 and (step_num/10):
			count += 1
		if step_num  is 0 or step_num > n2:
			continue
		last_digit = step_num % 10
		step_num1 = (step_num * 10) + last_digit + 1
		step_num2 = (step_num * 10) + last_digit - 1
		if last_digit is 0:
			q.append(step_num1)
		elif last_digit is 9:
			q.append(step_num2)
		else:
			q.append(step_num1)
			q.append(step_num2)
	return count		
			
def main():
	count = 0
	n1 = input("Enter value of n1:")
	n2 = input("Enter value of n2:")
	for i in range(10):
		count += step_num_count(n1, n2, i)
	print "Total stepping num :",count
	
main()

using System;
					
public class Program
{
	public static void Main()
		
	{
		int n= 10 ;
		int m = 100;
		Console.WriteLine(DisplaySteppingNumber(n ,m));
	}
	
	public static int DisplaySteppingNumber(int n ,int m)
	{
		int count = 0;
		for (int i = 1 ; i <= 9 ; i++)
		{
			findSteppingNum( n , m , i , ref count);
		}
		
		return count;
	}
	public static void findSteppingNum (int n , int m , int stepnum , ref int count)
	{
		if ( stepnum > m || stepnum == 0 )
			
		{
			return ;
		}
		if (stepnum > n )
		{
			count ++;
		}
		 int lastDigit = stepnum % 10;
 
		// There can be 2 cases either digit
		// to be appended is lastDigit + 1 or
		// lastDigit - 1
		int stepnumA = stepnum*10 + (lastDigit-1);
		int stepnumB = stepnum*10 + (lastDigit+1);
		
		
		// If lastDigit is 0 then only possible
		// digit after 0 can be 1 for a Stepping
		// Number
		if (lastDigit == 0)
			findSteppingNum(n, m, stepnumB , ref count);
 
		// If lastDigit is 9 then only possible
		// digit after 9 can be 8 for a Stepping
		// Number
		else if(lastDigit == 9)
        findSteppingNum(n, m, stepnumA , ref count);
		else
		{
			 findSteppingNum(n, m, stepnumA , ref count);
			 findSteppingNum(n, m, stepnumB , ref count);
		}
	}
}

using System;
					
public class Program
{
	public static void Main()
		
	{
		int n= 10 ;
		int m = 100;
		Console.WriteLine(DisplaySteppingNumber(n ,m));
	}
	
	public static int DisplaySteppingNumber(int n ,int m)
	{
		int count = 0;
		for (int i = 1 ; i <= 9 ; i++)
		{
			findSteppingNum( n , m , i , ref count);
		}
		
		return count;
	}
	public static void findSteppingNum (int n , int m , int stepnum , ref int count)
	{
		if ( stepnum > m || stepnum == 0 )
			
		{
			return ;
		}
		if (stepnum > n )
		{
			count ++;
		}
		 int lastDigit = stepnum % 10;
 
		// There can be 2 cases either digit
		// to be appended is lastDigit + 1 or
		// lastDigit - 1
		int stepnumA = stepnum*10 + (lastDigit-1);
		int stepnumB = stepnum*10 + (lastDigit+1);
		
		
		// If lastDigit is 0 then only possible
		// digit after 0 can be 1 for a Stepping
		// Number
		if (lastDigit == 0)
			findSteppingNum(n, m, stepnumB , ref count);
 
		// If lastDigit is 9 then only possible
		// digit after 9 can be 8 for a Stepping
		// Number
		else if(lastDigit == 9)
        findSteppingNum(n, m, stepnumA , ref count);
		else
		{
			 findSteppingNum(n, m, stepnumA , ref count);
			 findSteppingNum(n, m, stepnumB , ref count);
		}
	}
}