Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and num2, also represented as a string.
Example 1:
Input: num1 = "2", num2 = "3"
Output: "6"
Example 2:
Input: num1 = "123", num2 = "456"
Output: "56088"
Note:
       The length of both num1 and num2 is < 110.
       Both num1 and num2 contain only digits 0-9.
       Both num1 and num2 do not contain any leading zero, except the number 0 itself.
       You must not use any built-in BigInteger library or convert the inputs to integer directly.
class Solution:
     def multiply(self,num1, num2):
         a=['0','1','2','3','4','5','6','7','8','9']
         z=0
         x=0
         for i,element in enumerate(num1):
             for j in range(10):
                 if element==a[j]:
                     z+=j*(10**(len(num1)-i-1))
                     
         for c,b in enumerate(num2):
             for k in range(10):
                 if b==a[k]:
                     x+=k*(10**(len(num2)-c-1))
         mul=z*x
         return(''.join('%d'%mul))
                     
  
        
             
         

class Solution:
     def multiply(self,num1, num2):
         a=['0','1','2','3','4','5','6','7','8','9']
         z=0
         x=0
         for i,element in enumerate(num1):
             for j in range(10):
                 if element==a[j]:
                     z+=j*(10**(len(num1)-i-1))
                     
         for c,b in enumerate(num2):
             for k in range(10):
                 if b==a[k]:
                     x+=k*(10**(len(num2)-c-1))
         mul=z*x
         return(''.join('%d'%mul))
                     
  
        
             
         
