def test(self):
test_a = [1, 3, 4, 6, 7]
get_result = binary_search(test_a, key=6)
self.assertEqual(get_result[0], True, msg="Searching Fail")
self.assertEqual(get_result[1], 3, msg="Invalid index")
test_b = [10, 20, 30, 40, 50]
get_result = binary_search(test_b, key=6)
self.assertEqual(get_result[0], False, msg="Searching Fail")
self.assertEqual(get_result[1], None, msg="Invalid index")
def val_in_list(input_list, input_val):
val_index = binary_search(input_list, input_val)
if(val_index != -1):
print str(input_val) + " found at index " + str(val_index) + "!"
return True
else:
print str(input_val) + " not found in input list"
return False
def exponential_search(arr: [int], key: int) -> int:
"""
Performs exponential search over given array.
Performs great in unbounded array and when element to be searched is closer to starting index.
Time complexity : O(log(n))
:param arr: Sorted input array.
:param key: Value to be found out.
:return: Index of key if it is present in the array else -1.
"""
# Calculate the length of array.
n = len(arr)
# Check if first element matches the key.
if arr[0] == key:
return 0
# Find index i where arr[i] > key.
i = 1
while i < n and arr[i] <= key:
i = i * 2
# Perform binary search over the target array.
return binary_search(arr, key, int(i / 2), min(i, n - 1))
def test1(self):
arr = [1, 2, 3, 4, 5, 6, 7]
val = 4
assert binary_search(arr, val) == True
def test4(self):
arr = [1, 2, 3, 4, 5, 6, 7]
val = 9
assert binary_search(arr, val) == False
def test_binary_search(self):
foo = [1,32,56,84,97,105,325,725]
self.assertEqual(binary_search(foo, 32), True)