Practical_12(part1)(python).py

'''
Write a python program to store names and mobile numbers of your friends in sorted 
order on names. Search your friend from list using binary search (recursive and nonrecursive). Insert friend if not present in phonebook
'''

class Friend:
    def __init__(self, name, mobile_number):
        self.name = name
        self.mobile_number = mobile_number

def binary_search_recursive(friends, name, low, high):
    if low > high:
        return None

    mid = (low + high) // 2
    if friends[mid].name == name:
        return friends[mid]
    elif friends[mid].name > name:
        return binary_search_recursive(friends, name, low, mid - 1)
    else:
        return binary_search_recursive(friends, name, mid + 1, high)

def binary_search_non_recursive(friends, name):
    low = 0
    high = len(friends) - 1

    while low <= high:
        mid = (low + high) // 2
        if friends[mid].name == name:
            return friends[mid]
        elif friends[mid].name > name:
            high = mid - 1
        else:
            low = mid + 1

    return None

def insert_friend(friends, name, mobile_number):
    friend = binary_search_non_recursive(friends, name)

    if friend is None:
        new_friend = Friend(name, mobile_number)
        friends.append(new_friend)
        friends.sort(key=lambda x: x.name)

def main():
    friends = [Friend("Alice", "1234567890"),
               Friend("Bob", "0987654321"),
               Friend("Charlie", "9876543210"),
               Friend("David", "5432167890")]

    # Sorting friends list based on names
    friends.sort(key=lambda x: x.name)

    print("Friends List:")
    for friend in friends:
        print(f"{friend.name}: {friend.mobile_number}")

    # Searching friends using binary search recursive
    search_name = "Bob"
    friend_recursive = binary_search_recursive(friends, search_name, 0, len(friends)-1)
    if friend_recursive is not None:
        print(f"\nFriend found (recursive): {friend_recursive.name}, {friend_recursive.mobile_number}")
    else:
        print(f"\nFriend not found (recursive)")

    # Searching friends using binary search non-recursive
    search_name = "Charlie"
    friend_non_recursive = binary_search_non_recursive(friends, search_name)
    if friend_non_recursive is not None:
        print(f"\nFriend found (non-recursive): {friend_non_recursive.name}, {friend_non_recursive.mobile_number}")
    else:
        print(f"\nFriend not found (non-recursive)")

    # Inserting a friend if not present in phonebook
    insert_friend(friends, "Eve", "9876543210")
    insert_friend(friends, "Bob", "5555555555")

    print("\nUpdated Friends List:")
    for friend in friends:
        print(f"{friend.name}: {friend.mobile_number}")

if __name__ == "__main__":
    main()