Find the Difference in C++

Suppose we have two strings s and t which consist of only lowercase letters. Now, string t is generated by random shuffling string s and then add one more letter at a random index. We have to find the letter that was added in t.

So, if the input is like "mnopq","pqmnot", then the output will be "t", this is the extra letter.

To solve this, we will follow these steps −

sSum := 0, tSum := 0
for initialize i := 0, when i < call length() of s, update (increase i by 1), do −
- sSum := sSum + s[i]
for initialize j := 0, when j < call length() of t, update (increase j by 1), do −
- tSum := tSum + t[j]
return (tSum - sSum) as character

Example

Let us see the following implementation to get better understanding −

#include <bits/stdc++.h>
using namespace std;
class Solution {
public:
   char findTheDifference(string s, string t) {
      int sSum = 0;
      int tSum = 0;
      for (int i = 0; i < s.length(); i++) {
         sSum += s[i];
      }
      for (int j = 0; j < t.length(); j++) {
         tSum += t[j];
      }
      return char(tSum - sSum);
   }
};
main(){
   Solution ob;
   cout << (ob.findTheDifference("mnopq","pqmnot"));
}

Input

"mnopq","pqmnot"

Output