Typical Programs in C/C++
Sum of two large numbers Difficulty Level : Medium Last Updated : 04 Jun, 2019 Given two numbers as strings. The numbers may be very large (may not fit in long long int), the task is to find sum of these two numbers. Examples: Input : str1 = "3333311111111111", str2 = "44422222221111" Output : 3377733333332222 Input : str1 = "7777555511111111", str2 = "3332222221111" Output : 7780887733332222 The idea is based on school mathematics. We traverse both strings from end, one by one add digits and keep track of carry. To simplify the process, we do following: 1) Reverse both strings. 2) Keep adding digits one by one from 0’th index (in reversed strings) to end of smaller string, append the sum % 10 to end of result and keep track of carry as sum/10. 3) Finally reverse the result. // C++ program to find sum of two large numbers. #include<bits/stdc++.h> using namespace std; // Function for finding sum of la