Remove All Adjacent Duplicates In String- solve using stack

remove_dups.cpp

string removeDuplicates(string toCleanUp) {
    std:stack< char > str_stack;

    for(char x : toCleanUp) {
        if( !str_stack.empty() && x == str_stack.top() ) str_stack.pop();
        else str_stack.push( x );
        
    }
    string res;
    res.reserve(str_stack.size()); // reserve the space so that the concatenation speeds up.
    while( !str_stack.empty() ) {
        res += str_stack.top();
        str_stack.pop();
    }
    reverse(res.begin(), res.end());
    return res;
}