Python Program / Project - 19

Question 19: Write a Python program to maintain club members, sort on roll numbers in ascending order. Write function “Ternary_Search” to search whether particular student is member of club or not. Ternary search is modified binary search that divides array into 3 halves instead of two.

Download hole Program / Project code, by clicking following link:

go2collage/Python-Programs-and-Projects-19 (github.com)

In if-else construct which part will be executed if condition is ture in Java ?

In an if-else construct in Java, the code within the if block will be executed if the condition specified in the if statement is true. If the if condition is false, then the code within the else block (if an else block is provided) will be executed.

Programming Code:

Following code write in: DS_P19.py

# Python Program / Project 

def accept_roll():
    rollno = []
    students = int(input("Enter number of students: "))
    for i in range(students):
        roll = int(input("Enter Roll number: "))
        rollno.append(roll)
    return rollno

def print_roll(rollno):
    for i in range(len(rollno)):
        print(rollno)
        break

def ins_sort(rollno):
    for i in range(len(rollno)):
        key = rollno[i]
        j = i - 1
        while j>=0 and key < rollno[j]:
            rollno[j+1] = rollno[j]
            j -= 1 
            rollno[j+1] = key
    return rollno

def nr_ternarysearch(sort_roll, find_roll):
    left = 0
    right = len(sort_roll) - 1
    while left <= right:
        mid1 = left + (right-left) //3
        mid2 = left + 2 * (right - left) // 3
        if find_roll == sort_roll[left]:
            return left
        elif find_roll == sort_roll[right]:
            return right
        elif find_roll < sort_roll[left] or find_roll > sort_roll[right]:
            return -1
        elif find_roll <= sort_roll[mid1]:
            right = mid1
        elif find_roll > sort_roll[mid1] and find_roll <= sort_roll[mid2]:
            left = mid1+1
            right = mid2
        else:
            left = mid2 + 1
    return -1

def r_ternarysearch(sort_roll,left, right, find_roll):
    if (right >= left):
        mid1 = left + (right-left) //3
        mid2 = right - (right - left) // 3
        if(sort_roll[mid1] == find_roll):
            return mid1
        if (sort_roll[mid2] == find_roll):
            return mid2

        if(find_roll < sort_roll[mid1]):
            return r_ternarysearch(sort_roll,left, mid1-1, find_roll)
        elif find_roll > sort_roll[mid2]:
            return r_ternarysearch(sort_roll,mid2+1, right, find_roll)
        else:
            return r_ternarysearch(sort_roll,mid1+1, mid2+1, find_roll)
    return -1

# Driver Code

unsort_roll = []
sort_roll = []

while (True):
    print("************ Menu ************")
    print("1. Accept Students roll numbers. ")
    print("2. Display the Students roll numbers. ")
    print("3. Sort roll numbers from the list.")
    print("4. Perform Non-Recursive Ternary Search.")
    print("5. Perform Recursive Ternary Search.")
    print("6. Exit.")

    choice = int(input("Enter your choice: "))
    if choice == 1:
        unsort_roll = accept_roll()
    elif choice == 2:
        print_roll(unsort_roll)
    elif choice == 3:
        print("Elements after performing sort operation: ")
        sort_roll =  ins_sort(unsort_roll)
        print(sort_roll)
    elif choice == 4:
        find_roll = int(input("Enter the Roll number to search: "))
        index = nr_ternarysearch(sort_roll, find_roll)
        if index != -1:
            print("Roll number found.")
        else:
            print("Roll number not found.")
    elif choice == 5:
        find_roll = int(input("Enter the Roll number to search: "))
        left = 0
        right = len(sort_roll) - 1
        index = r_ternarysearch(sort_roll,left, right, find_roll)
        if index != -1:
            print("Roll number found.")
        else:
            print("Roll number not found.")

    else:
        print("You have exit.")
        exit()

# Thanks For Reading.

Output: