We have added some beginners interview question for Python Programming Language. Once, you are comfortable with easy to achieve guide we will add more advanced interview questions as well.

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** Question:** Given an array

**Arr**(distinct elements) of size

**N**. Rearrange the elements of array in zig-zag fashion. The converted array should be in form

**a < b > c < d > e < f.**The relative order of elements is same in the output

**i.e**you have to iterate on the original array only.

**Example 1:**

**Input:
**N = 7
Arr[] = {4, 3, 7, 8, 6, 2, 1}
**Output: **3 7 4 8 2 6 1
**Explanation:** 3 < 7 > 4 < 8 > 2 < 6 > 1

**Example 2:**

**Input:
**N = 4
Arr[] = {1, 4, 3, 2}
**Output:** 1 4 2 3
**Explanation: **1 < 4 > 2 < 3

Your task is to complete the function **zigZag()** which takes the array of integers **array **and **n **as parameters and returns void. You need to modify the array itself.**NOTE:** In the mentioned complexity, only a unique solution will exist.

**Expected Time Complexity:** O(N)**Expected Auxiliary Space:** O(1)

**Constraints:**

1 <= N <= 10^{5}

0 <= Arr_{i} <= 10^{6}

*Problem Walkthrough *

*Solution*

```
def zigZag(arr, n):
flag = True
for i in range(n - 1):
# "<" relation expected
if flag is True:
# If we have a situation like
# A > B > C, we get A > B < C
# by swapping B and C
if arr[i] > arr[i + 1]:
arr[i], arr[i + 1] = arr[i + 1], arr[i]
# ">" relation expected
else:
# If we have a situation like
# A < B < C, we get A < C > B
# by swapping B and C
if arr[i] < arr[i + 1]:
arr[i], arr[i + 1] = arr[i + 1], arr[i]
flag = bool(1 - flag)
print(arr)
# Print Output
arr = [4, 3, 7, 8, 6, 2, 1]
n = len(arr)
zigZag(arr, n)
```

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