Word Pattern Matching

#include <bits/stdc++.h>
using namespace std;

void wordPattern(string s, int index, string &str1, string &str2, unordered_set<char> &uniqueSet, unordered_map<char, string> &mapping){
    if(index >= str2.size()){
        string stringFormed = "";
        for(char c : str2){
            stringFormed += mapping[c];
        }
        if(stringFormed == str1){
            for(char c : str2){
                cout << c << ": " << mapping[c] << " ";
            }
            cout << '\n';
        }
        return;
    }
    if(s == ""){
        return;
    }
    if(uniqueSet.count(str2[index]) == 0){
        for(int i = 1; i < s.size(); i++){
            string substring = s.substr(0, i);
            string ros = s.substr(i);
            mapping[str2[index]] = substring;
            uniqueSet.insert(str2[index]);
            wordPattern(ros, index + 1, str1, str2, uniqueSet, mapping);
            uniqueSet.erase(str2[index]);
        }
        mapping.erase(str2[index]);
    }
    else{
        wordPattern(s, index + 1, str1, str2, uniqueSet, mapping);
    }
}

int main() {
    // your code goes here
    string str1, str2;
    cin >> str1 >> str2;
    unordered_set<char> uniqueSet;
    unordered_map<char, string> mapping;
    wordPattern(str1, 0, str1, str2, uniqueSet, mapping);
}