def inplace_quick_sort(S, a, b): 
    if a >= b: 
        return 
    pivot = S[b] 
    left = a 
    right = b - 1 
    while left <= right: 
        while left <= right and S[left] < pivot: 
            left += 1 
        while left <= right and S[right] > pivot: 
            right -= 1 
        if left <= right: 
            S[left], S[right] = S[right], S[left] 
            left += 1 
            right -= 1 
 
    S[left], S[b] = S[b], S[left] 
    inplace_quick_sort(S, a, left - 1) 
    inplace_quick_sort(S, left + 1, b) 
 
 
while True: 
    S = [] 
    print("\tImplementation of In-place Quick-Sort algorithm using List") 
 
    n = int(input("\nEnter number of elements (greater than Zero): ")) 
    if n >= 1: 
        print("Enter the elements one by one:") 
        for i in range(n): 
            S.append(int(input())) 
 
 
 
        print("\nOutput") 
        print("-------") 
        print("\nElements before sorting:") 
        print(S) 
 
        inplace_quick_sort(S, 0, len(S) - 1) 
 
        print("\nElements after sorting:") 
        print(S) 
    else: 
        print("Invalid Input!") 
 
    c = int(input("\nTo continue press 1 otherwise press 0... ")) 
    if c != 1: 
        print("Program Terminated") 
        break