**Zig Zag Sequence**

### Problem Statement :

In this challenge, the task is to debug the existing code to successfully execute all provided test files. Given an array of n distinct integers, transform the array into a zig zag sequence by permuting the array elements. A sequence will be called a zig zag sequence if the first k elements in the sequence are in increasing order and the last k elements are in decreasing order, where k = ( n+1) /2 . You need to find the lexicographically smallest zig zag sequence of the given array. Note: You can modify at most three lines in the given code. You cannot add or remove lines of code. To restore the original code, click on the icon to the right of the language selector. Input Format The first line contains t the number of test cases. The first line of each test case contains an integer n, denoting the number of array elements. The next line of the test case contains n elements of array a. Constraints 1 <= t <= 20 1 <= n <= 10000 ( n is always odd) 1 <= ai <= 10^9 Output Format For each test cases, print the elements of the transformed zig zag sequence in a single line.

### Solution :

` ````
Solution in C :
In Python3 :
def findZigZagSequence(a, n):
a.sort()
mid = int((n + 1)/2)-1#1st change
a[mid], a[n-1] = a[n-1], a[mid]
st = mid + 1
ed = n - 2#2nd change
while(st <= ed):
a[st], a[ed] = a[ed], a[st]
st = st + 1
ed = ed - 1 #3rd change
for i in range (n):
if i == n-1:
print(a[i])
else:
print(a[i], end = ' ')
return
In Java :
// first change
int mid = (n+1)/2 - 1;
// second change
int ed = n - 2;
//third change
ed = ed - 1;
```

## View More Similar Problems

## Is This a Binary Search Tree?

For the purposes of this challenge, we define a binary tree to be a binary search tree with the following ordering requirements: The data value of every node in a node's left subtree is less than the data value of that node. The data value of every node in a node's right subtree is greater than the data value of that node. Given the root node of a binary tree, can you determine if it's also a

View Solution →## Square-Ten Tree

The square-ten tree decomposition of an array is defined as follows: The lowest () level of the square-ten tree consists of single array elements in their natural order. The level (starting from ) of the square-ten tree consists of subsequent array subsegments of length in their natural order. Thus, the level contains subsegments of length , the level contains subsegments of length , the

View Solution →## Balanced Forest

Greg has a tree of nodes containing integer data. He wants to insert a node with some non-zero integer value somewhere into the tree. His goal is to be able to cut two edges and have the values of each of the three new trees sum to the same amount. This is called a balanced forest. Being frugal, the data value he inserts should be minimal. Determine the minimal amount that a new node can have to a

View Solution →## Jenny's Subtrees

Jenny loves experimenting with trees. Her favorite tree has n nodes connected by n - 1 edges, and each edge is ` unit in length. She wants to cut a subtree (i.e., a connected part of the original tree) of radius r from this tree by performing the following two steps: 1. Choose a node, x , from the tree. 2. Cut a subtree consisting of all nodes which are not further than r units from node x .

View Solution →## Tree Coordinates

We consider metric space to be a pair, , where is a set and such that the following conditions hold: where is the distance between points and . Let's define the product of two metric spaces, , to be such that: , where , . So, it follows logically that is also a metric space. We then define squared metric space, , to be the product of a metric space multiplied with itself: . For

View Solution →## Array Pairs

Consider an array of n integers, A = [ a1, a2, . . . . an] . Find and print the total number of (i , j) pairs such that ai * aj <= max(ai, ai+1, . . . aj) where i < j. Input Format The first line contains an integer, n , denoting the number of elements in the array. The second line consists of n space-separated integers describing the respective values of a1, a2 , . . . an .

View Solution →