binary_search.py

'''
Kyle C. Rosales (DarkPotatoKing)
October 8, 2014
Binary Search
'''
def binary_search(ls, val):
    ls.sort()
    start, end = 0, len(ls) - 1
    while start != end:
        mid = start + (end - start) / 2
        if ls[mid] == val: return mid
        elif ls[mid] < val: start, end = mid + 1, end
        else: start, end = start, mid - 1
    return start if ls[start] == val else -1