Jump search (#2415)

* jump_search: doctest, docstring, type hint, inputs

* jumpsearch.py: case number not found

* trailing whitespace jump search
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Guillaume Rochedix 2020-09-12 07:50:12 +02:00 committed by GitHub
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commit f754c0d31f
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@ -1,7 +1,28 @@
"""
Pure Python implementation of the jump search algorithm.
This algorithm iterates through a sorted collection with a step of n^(1/2),
until the element compared is bigger than the one searched.
It will then perform a linear search until it matches the wanted number.
If not found, it returns -1.
"""
import math
def jump_search(arr, x):
def jump_search(arr: list, x: int) -> int:
"""
Pure Python implementation of the jump search algorithm.
Examples:
>>> jump_search([0, 1, 2, 3, 4, 5], 3)
3
>>> jump_search([-5, -2, -1], -1)
2
>>> jump_search([0, 5, 10, 20], 8)
-1
>>> jump_search([0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610], 55)
10
"""
n = len(arr)
step = int(math.floor(math.sqrt(n)))
prev = 0
@ -21,6 +42,11 @@ def jump_search(arr, x):
if __name__ == "__main__":
arr = [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610]
x = 55
print(f"Number {x} is at index {jump_search(arr, x)}")
user_input = input("Enter numbers separated by a comma:\n").strip()
arr = [int(item) for item in user_input.split(",")]
x = int(input("Enter the number to be searched:\n"))
res = jump_search(arr, x)
if res == -1:
print("Number not found!")
else:
print(f"Number {x} is at index {res}")