# 43. Multiply Strings

## 27 Dec 43. Multiply Strings

Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and num2, also represented as a string.

Note: You must not use any built-in BigInteger library or convert the inputs to integer directly.

Example 1:

Input: num1 = "2", num2 = "3"
Output: "6"

Example 2:

Input: num1 = "123", num2 = "456"
Output: "56088"

Constraints:

• 1 <= num1.length, num2.length <= 200
• num1 and num2 consist of digits only.
• Both num1 and num2 do not contain any leading zero, except the number 0 itself.

class Solution:
def multiply(self, num1: str, num2: str) -> str:
if num1 == ‘0’ or num2 ==’0′:
return ‘0’

def strToInt(num):
return_value = 0
for i in num:
return_value = return_value * 10 + (ord(i) – ord(‘0’))
return return_value

def intToStr(num):
return_str = ”
while num:
s = num % 10
num = num // 10
return_str = chr(ord(‘0’)+s) + return_str
return return_str

result = intToStr(strToInt(num1) * strToInt(num2))
return result