Remove trailing zeros from the sum of two numbers ( Using Stack )

Given two numbers A and B, the task is to remove the trailing zeros present in the sum of the two given numbers using a stack.

Examples:

Input: A = 124, B = 186
Output: 31
Explanation: Sum of A and B is 310. Removing the trailing zeros modifies the sum to 31.

Input: A=130246, B= 450164
Output : 58041

Approach: The given problem can be solved using the string and stack data structures. Follow the steps below to solve the problem:

• Calculate A + B and store it in a variable, say N.
• Initialize a stack < char >, say S, to store the digits of N.
• Convert the integer N to string and then push the characters into the stack S.
• Iterate while S is not empty(), If the top element of the stack is '0', then pop it out of the stack. Otherwise, break.
• Initialize a string, say res, to store the resultant string.
• Iterate while S is not empty(), and push all the characters in res and, then pop the top element.
• Reverse the string res and print the res as the answer.

Below is the implementation of the above approach:

58041

Time Complexity: O(len(A + B))
Auxiliary Space: O(len(A + B))