How to solve Backspace String Compare in c++?

Backspace String Compare

Backspace String Compare

Code for comparing two strings after applying backspace by Bob and Alice users. where backspace is '#';

#include <iostream>
#include <string>
using namespace std;

bool userLogic(string bob, string alice) {
    // no of elemnts typed by persons
    int sIndex = bob.size();
    int tIndex = alice.size();
    // to track backspace count 
    int sBackspaceCount = 0;
    int tBackspaceCount = 0;

    while(sIndex >=0 || tIndex >=0){
        
        while(sIndex >=0){
        if(bob[sIndex]=='#'){
            sBackspaceCount++;
            sIndex--;
        }else if(sBackspaceCount>0){
            sBackspaceCount--;
            sIndex--;
        }else{
            break;
        }
        }
        while(tIndex >=0){

        if(alice[tIndex]=='#'){
            tBackspaceCount++;
            tIndex--;
        }else if(tBackspaceCount>0){
            tBackspaceCount--;
            tIndex--;
        }else{
            break;
        }
        }
        if(sIndex >=0 && tIndex >= 0){
            if(bob[sIndex] != alice[tIndex]){
                return false;
            }
            }else if(sIndex >=0 ||tIndex >=0){
                return false;
            }
            sIndex--;
            tIndex--;
        
    }
    return true; // or false
}

int main() {
    string bob, alice;
    getline(cin, bob);
    getline(cin, alice);
    bool result = userLogic(bob, alice);
    cout << (result ? "YES" : "NO") << endl;
    return 0;
}
 

In this code, the two persons type backspace and letter where backspace is indicated with '#'. You will remove the character before the backspace.

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