DataStructuresAndAlgorithms/Practical-B11.cpp

#include <iostream>
using namespace std;

class node {
public:
    string word;
    string meaning;
    node* left;
    node* right;

    node(string x, string y) {
        word = x;
        meaning = y;
        left = NULL;
        right = NULL;
    }

    friend class Dictionary;
};

class Dictionary {
public:
    node* root, * q;    // q is parent here
    Dictionary() {
        root = NULL;
        q = NULL;
    }

    void insert(node*, string, string);
    void display_asc(node*);
    void display_desc(node*);
    void comparisons(node*, string);
    void updateWord(node*, string);
    void deleteWord(node*&, string);
    node* min_node(node*);
};

void Dictionary::insert(node* p, string key, string keyMeaning) {
    if (key < p->word) {
        if (p->left != NULL)
            insert(p->left, key, keyMeaning);
        else
            p->left = new node(key, keyMeaning);
    }
    else if (key > p->word) {
        if (p->right != NULL)
            insert(p->right, key, keyMeaning);
        else
            p->right = new node(key, keyMeaning);
    }
}

void Dictionary::display_asc(node* p) {        //inorder
    if (p->left != NULL)
        display_asc(p->left);
    cout << "\n" << p->word << " \t" << p->meaning;
    if (p->right != NULL)
        display_asc(p->right);
}

void Dictionary::display_desc(node* p) {
    if (p->right != NULL)
        display_desc(p->right);
    cout << "\n" << p->word << " \t" << p->meaning;
    if (p->left != NULL)
        display_desc(p->left);
}

void Dictionary::comparisons(node* p, string key) {
    static int count = 0;
    while (p != NULL) {
        if (key < p->word) {
            count++;
            p = p->left;
        }

        else if (key > p->word) {
            count++;
            p = p->right;
        }

        else if (key == p->word) {
            count++;
            cout << "Number of comparisons to find the word: " << count;
            return;
        }
    }

    cout << "\nWord not found!";
}

node* Dictionary::min_node(node* p) {
    while (p->left != NULL) {
        q = p;
        p = p->left;
    }
    return p;
}

void Dictionary::deleteWord(node*& p, string key) {
    node* s;
    while (p != NULL) {                            //searching for word
        if (key < p->word) {
            q = p;
            p = p->left;
        }

        else if (key > p->word) {
            q = p;
            p = p->right;
        }

        else if (key == p->word) {                //word found
            if (p->left == NULL && p->right == NULL) {    //no child
                if (q->left == p) {
                    delete p;
                    q->left = NULL;
                    return;
                }

                if (q->right == p) {
                    delete p;
                    q->right = NULL;
                    return;
                }

            }

            if (p->right != NULL && p->left == NULL) {    //right child only
                if (q->right == p) {
                    q->right = p->right;
                    delete p;
                    return;
                }

                else if (q->left == p) {
                    q->left = p->right;
                    delete p;
                    return;
                }

            }

            else if (p->left != NULL && p->right == NULL) {    //left child only
                if (q->right == p) {
                    q->right = p->left;
                    delete p;
                    return;
                }

                else if (q->left == p) {
                    q->left = p->left;
                    delete p;
                    return;
                }

            }

            else if (p->left != NULL && p->right != NULL) {
                s = min_node(p->right);
                p->word = s->word;
                p->meaning = s->meaning;
                deleteWord(p->right, s->word);
                return;

            }
        }
    }
    cout << "\nWord NOT found!";
}

void Dictionary::updateWord(node* p, string key) {
    while (p != NULL) {
        if (key < p->word)
            p = p->left;

        else if (key > p->word)
            p = p->right;

        else if (key == p->word) {
            cout << "\nEnter its new meaning: ";
            cin >> p->meaning;
            return;
        }
    }
    cout << "\nWord not found!";
}

int main() {
    int choice, n;
    string newWord, searchWord, newMeaning;
    Dictionary d1;
    menu:
    cout << "\n\nDICTIONARY: ";
    cout << "\n\n1. Insert new words";
    cout << "\n2. Display the dictionary in Ascending order";
    cout << "\n3. Display the dictionary in Descending order";
    cout << "\n4. Search and update a word";
    cout << "\n5. Delete a word";
    cout << "\n6. Compare";
    cout << "\n7. EXIT";
    cout << "\n\nEnter your choice: ";
    cin >> choice;
    switch (choice) {
    case 1:
        cout << "\nEnter the number of words to insert: ";
        cin >> n;
        for (int i = 0; i < n; i++) {
            cout << "\nEnter the word to be inserted: ";
            cin >> newWord;
            cout << "\nEnter its meaning: ";
            cin >> newMeaning;
            if (d1.root == NULL)
                d1.root = new node(newWord, newMeaning);
            else
                d1.insert(d1.root, newWord, newMeaning);
        }
        break;

    case 2:
        d1.display_asc(d1.root);
        break;

    case 3:
        d1.display_desc(d1.root);
        break;

    case 4:
        cout << "\nEnter the word to search: ";
        cin >> searchWord;
        d1.updateWord(d1.root, searchWord);
        break;

    case 5:
        cout << "\nEnter the word to delete: ";
        cin >> searchWord;
        d1.deleteWord(d1.root, searchWord);
        break;

    case 6:
        cout << "\nEnter the word to find comparisons: ";
        cin >> searchWord;
        d1.comparisons(d1.root, searchWord);
        break;
        
   case 7:
       cout << "END OF THE CODE .";
       break;     

    default:
        cout << "\nInvalid input!!!...Enter a Valid Input.";
    }
    if (choice != 8)
        goto menu;
    return 0;
}