iterative binary_search

binary_search.py

def binary_search(arr, target):
    low, high = 0, len(arr) - 1
    while low <= high:
        mid = (low+high) // 2
        if arr[mid] > target:
            high = mid -1
        elif arr[mid] == target:
            return mid
        else:
            low = mid + 1
    return -1