give an array n and integer k, for each element in the array, you have to whether +k or -k. try to find the minimum gap between the largest value and smallest value after the operations

yaoxuan.py

#!/usr/bin/env python

"""
give an array n and integer k, for each element in the array, you have to whether +k or -k
try to find the minimum gap between the largest value and smallest value after the operations
"""

def find1(arr, k):
    arr2 = []
    for i in xrange(0, len(arr)):
        arr2.append((arr[i] - k, i))
        arr2.append((arr[i] + k, i))
    arr2.sort()

    min_gap = arr2[-1][0] - arr2[0][0]

    for i in xrange(0, len(arr2)):
        min_value, max_value = arr2[i][0], arr2[i][0]
        elements = {}
        for j in xrange(i, len(arr2)):
            elements[arr2[j][1]] = True
            max_value = arr2[j][0]
            if len(elements) == len(arr):
                break
        if len(elements) == len(arr):
            min_gap = min(min_gap, max_value - min_value)

    return min_gap

if __name__ == "__main__":
    print find1([0, 2, 4, 10], 3)
    print find1([1, 2, 3], 100)