#!/usr/bin/env python

# Given an array of integer and a specific integer value (e.g: 4) you need to
# move all the integer with that value (in the array) at the beginning of the
# array. The order of the other elements must not change.

import random

def pack(array, n):
    src = dest = len(array) - 1

    while src >= 0:
        while src >= 0 and array[src] == n:
            src -= 1
        if src >= 0 and src != dest:
            array[dest] = array[src]
        src -= 1
        dest -= 1

    while dest != -1:
        array[dest] = n
        dest -= 1

array = [random.choice(range(10)) for i in range(15)]
n = random.choice(range(10))
print("array = {0}, n = {1}".format(array, n))
pack(array, n)
print("array = {0}".format(array))
print("****")
array = [7, 9, 0, 8, 2, 3, 9, 9, 9, 2, 5, 6, 6, 0, 1]
n = 9
print("array = {0}, n = {1}".format(array, n))
pack(array, n)
print("array = {0}".format(array))