PhoneBook

#include <iostream>
#include <string.h>
#include <cctype>

using namespace std;

class Node {
public:
    char name[30];
    char number[20];
    Node* nextLink;
    Node* prevLink;
    
    Node(char n[], char num[])
    {
        strcpy(name,n);
        strcpy(number, num);
        nextLink = NULL;
        prevLink = NULL;
    }
    friend class contactList;
};

class contactList {
    Node* head, * temp, * ptr;

public:
    void insert();
    void sort();
    void deletecontact(char n[30]);
    void searchbyname(char p[30]);
    void searchbynumber(char num[20]);
    void takeInput();
    void display();
    void update(char a[30]);
};

void contactList::takeInput() {
    char name[30];
    char number[20];
    char c;
    do {
    	system("cls");
        cout << "\nEnter Name: ";
        cin.sync();
        cin.getline(name,30);
        cout << "\nEnter Phone Number: ";
        cin >> number;
        while (strlen(number) != 10) {
            cout << "Enter Valid Phone Number";
            cin >> number;
        }
        temp = new Node(name, number);
        if (head == NULL)
        {
            head = temp;
        }
        else
        {
            ptr = head;
            while (ptr->nextLink != NULL)
            {
                ptr = ptr->nextLink;
            }
            ptr->nextLink = temp;
            temp->prevLink = ptr;
        }
        cout << "\nDo you wish to continue?\n";
        cin >> c;
    } while (c == 'y' || c == 'Y');
    
}

void contactList::display() {
	system("cls");
    ptr = head;
    while (ptr != NULL)
    {
        cout << "Name: " << ptr->name << endl;
        cout << "Phone Number: " << ptr->number << endl;
        ptr = ptr->nextLink;
    }
}

void contactList::insert() {
    takeInput();
}

void contactList::sort() {
    Node* a, * b;
    int temp;
    char n[30];
    char no[20];
    for (a = head; a->nextLink != NULL; a = a->nextLink) {
        for (b = a->nextLink; b!=NULL; b = b->nextLink) {
            temp = strcmp(a->name, b->name);
            if (temp > 0) {
                //Swapping the names
                strcpy(n, a->name);
                strcpy(a->name, b->name);
                strcpy(b->name, n);
                strcpy(no, a->number);
                strcpy(a->number, b->number);
                strcpy(b->number, no);
            }
        }
    }
}

void contactList::deletecontact(char n[30]) {
    int c = 0;
    ptr = head;
    while (ptr != NULL) {
        if (strcmp(n, ptr->name) == 0) {
            c = 1;
            break;
        }
        else
            c = 2;
        ptr = ptr->nextLink;
    }
    if (c == 1 && ptr != head && ptr->nextLink != NULL) {
        ptr->prevLink->nextLink = ptr->nextLink;
        ptr->nextLink->prevLink = ptr->prevLink;
        delete(ptr);
        cout << "Contact Deleted Successfully!\n";
    }
    if (ptr == head) {
        head = head->nextLink;
        head->prevLink = NULL;
        delete(ptr);
        cout << "Contact Deleted Successfully!\n";
    }
    if (ptr->nextLink == NULL) {
        ptr->prevLink->nextLink = NULL;
        ptr->prevLink = NULL;
        delete(ptr);
        cout << "Contact Deleted Successfully!\n";
    }
    if(c==2)
        cout << "Name Not Found!\n";
}

void contactList::searchbyname(char p[30]) {
	system("cls");
    ptr = head;
    while (ptr != NULL) {
        if (strcmp(p, ptr->name) == 0) {
            cout << "Contact Found.\n";
            cout << "Name: " << ptr->name << endl;
            cout << "Phone Number: " << ptr->number << endl;
        }
        ptr = ptr->nextLink;
    }
}

void contactList::searchbynumber(char num[20]) {
	system("cls");
    ptr = head;
    while (ptr != NULL) {
        if (strcmp(num, ptr->number) == 0) {
            cout << "Contact Found.\n";
            cout << "Name: " << ptr->name << endl;
            cout << "Phone Number: " << ptr->number << endl;
        }
        ptr = ptr->nextLink;
    }
}

void contactList::update(char a[30]) {
	system("cls");
    char choice;
    int n;
    ptr = head;
    while (ptr != NULL) {
        if (strcmp(a, ptr->name) == 0) {
            do {
                cout << "Which type of information you want to Update?\n";
                cout << "1. Name\t2. Phone Number\n";
                cin >> n;
                switch (n) {
                case 1:
                    cout << "Enter New Name: ";
                    cin >> ptr->name;
                    break;

                case 2:
                    cout << "Enter New Phone Number: ";
                    cin >> ptr->number;
                    while (strlen(ptr->number) != 10) {
                        cout << "Enter a Valid Phone Number!\n";
                        cin >> ptr->number;
                    }
                    break;
                }
                cout << "Do you wish to continue?\n";
                cin >> choice;
            } while (choice == 'y' || choice == 'Y');
        }
        ptr=ptr->nextLink;
    }
}

int main()
{
    contactList c; //Creating object of contactList Class

    int choice,ch;
    char a;
    char name[30];
    char number[20];
    cout << "\t\t**********\n\t\tPHONE BOOK\n\t\t**********\n\n";
    cout << "Developed by Nitin Nishad\n*************************\n";
    cout << "\n\nEnter Username\n";
    cin.getline(name, 30);
    cout << "\n\nHello " << name<<", Let's get started.\n\n";
    system("cls");
    do {
    	cout << "\t\t**********\n\t\tPHONE BOOK\n\t\t**********\n\n";
        cout << "\n1. Add New Contact.\n2. Update Existing Contact.\n3. Display All Contacts.\n4. Search Contact\n5. Delete a Contact.\n6. Exit.\n\n";
        cin >> choice;
        switch (choice)
        {
        case 1:
        	system("cls");
            c.insert();
            c.sort();
            break;

        case 2:
        	system("cls");
            cout << "Enter Name: ";
            cin.sync();
            cin.getline(name, 30);
            c.update(name);
            c.sort();
            break;

        case 3:
        	system("cls");
            c.sort();
            c.display();
            break;

        case 4:
        	system("cls");
            do {
            	system("cls");
                cout << "1. Search by Name.\n2. Search by Phone Number.\n";
                cin >> ch;
                switch (ch) {
                case 1:
                    cout << "Enter Name: ";
                    cin.sync();
                    cin.getline(name, 30);
                    c.searchbyname(name);
                    break;

                case 2:
                    cout << "Enter Phone Number: ";
                    cin >> number;
                    c.searchbynumber(number);
                    break;
                }
                cout << "\nDo you wish to Continue?\n";
                cin >> a;
            } while (a == 'y' || a == 'Y');
            break;

        case 5:
        	system("cls");
                cout << "Enter Name to delete contact: ";
                cin.sync();
                cin.getline(name, 30);
                c.deletecontact(name);
                cout << "\nDo you wish to Continue?\n";
                break;
                
        case 6:
            exit(0);
            break;
        }
    } while (choice != 6);
}