added wiggle_sort.py (TheAlgorithms#734)

* Wiggle_sort

* Rename Wiggle_Sort to wiggle_sort.py

Author: Ishani08

sorts/wiggle_sort.py

@@ -0,0 +1,21 @@
+"""
+Given an unsorted array nums, reorder it such that nums[0] < nums[1] > nums[2] < nums[3]....  
+For example:
+if input numbers = [3, 5, 2, 1, 6, 4] 
+one possible Wiggle Sorted answer is [3, 5, 1, 6, 2, 4].
+"""
+def wiggle_sort(nums):
+    for i in range(len(nums)):
+        if (i % 2 == 1) == (nums[i-1] > nums[i]):
+            nums[i-1], nums[i] = nums[i], nums[i-1]
+
+
+print("Enter the array elements:\n")
+array=list(map(int,input().split()))
+print("The unsorted array is:\n")
+print(array)
+wiggle_sort(array)
+print("Array after Wiggle sort:\n")
+print(array)
+
+