Add jump search py (#29)

* Create jump-search.py

Added python implement jump search algorithm

* Update README.md

Updated README.md

* Updated jump-search.py

Added a check for sorted list in jump-search.

searching/README.md

@@ -10,6 +10,7 @@
 
 1. [Linear Search](python/linear-search.py)
 2. [Binary Search](python/binary-search.py)
+3. [Jump Search](python/jump-search.py) 
 
 ### JavaScript
 

searching/python/jump-search.py

@@ -0,0 +1,49 @@
+"""
+Jump search algorithm iterates through a sorted list with a step of n^(1/2),
+until the element compared is bigger than the one searched.If the item is not
+in the particular step, it shifts the entire step.
+It will then perform a linear search on the step until it matches the target.
+If not found, it returns -1.
+Time Complexity: O(√n)
+Space Complexity: O(1)
+"""
+
+import math
+
+
+def jump_search(arr: list, x: int) -> int:
+    n = len(arr)
+    step = int(math.floor(math.sqrt(n)))
+    prev = 0
+    while arr[min(step, n) - 1] < x:
+        prev = step
+        step += int(math.floor(math.sqrt(n)))
+        if prev >= n:
+            return -1
+    while arr[prev] < x:
+        prev = prev + 1
+        if prev == min(step, n):
+            return -1
+    if arr[prev] == x:
+        return prev
+    return -1
+
+def check_sort(test: list) -> bool:
+    """checks whether the given list is sorted or not."""
+    if sorted(test) == test:
+        return True
+    else:
+        return False
+
+
+if __name__ == "__main__":
+    arr = [0, 1, 2, 8, 13, 17, 19, 25, 31, 32, 42]
+    target = 25
+    if check_sort(arr):
+        res = jump_search(arr, target)
+        if res == -1:
+            print("Number not found!")
+        else:
+            print(f"Number {target} is at index {res}")
+    else:
+        print("Given list is not sorted!")