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How to compare strings?

SS Android (8)
Hello,

In short, I need to compare strings using the '<' operator. Ex: " if (foo< bar) std::cout << "foo is less than bar\n"; "

The way I understand it from "http://www.cplusplus.com/reference/string/string/operators/"
both the left-hand-side and the rhs of the operator have to be const string&
"bool operator< (const string& lhs, const string& rhs);
bool operator< (const char* lhs, const string& rhs);
bool operator< (const string& lhs, const char* rhs);"

In my code, I have a string value that is already a const string&, and a string value that is a string*.

The problem is, when I try to compare a const string& to a string*, I get an error.

I am new to this and barely understand what a const string& is, and why I cannot compare it to a string*.

Could you please help me in finding a way to compare these two strings for my BST insertion?


Here is my BST class
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  class BST
{
    public:
        BST();
        ~BST();
    
        void insertContent(const string& word, const string& definition);
        void deleteContent(string* word);
        const string* getContent(const string& word);
    
    private:
        class Node
        {
            public:
                Node(string* word, string* definition)
                {left=NULL; right=NULL; m_word=word; m_definition=definition;}
            
                Node* left;
                Node* right;
                string* m_word;
                string* m_definition;
        };



Here is the insert function where I need help comparing strings
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void BST::insertContent(const string& word, const string& definition)
{
    Node* ptr = root;
    //Node* entry = new Node(word, definition);
    
    if (root == NULL)
    {
        root = new Node(word, definition);
        return;
    }
    
    while (ptr != NULL)
    {
        const string& curwor = ptr->m_word; /*I was thinking of making my own const string& out of ptr->m_word but it didn't work. */
        
        if (word < ptr->m_word)
        {
            
        }
    }
}
keskiverto (10402)
In my code, I have a string value that is already a const string&, and a string value that is a string*.

The problem is, when I try to compare a const string& to a string*, I get an error.

No. You have a std::string (by reference) and you have a pointer.

You must dereference the pointer, if you want the object that the pointer points to.
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