arrangeNumArray.cpp

/*
You have been given an empty array(ARR) and
its size N. The only input taken from the user
will be N and you need not worry about the array.
Your task is to populate the array using the
integer values in the range 1 to N(both
inclusive) in the order - 1,3,5,.......,6,4,2.
Note:
You need not print the array. You only need
to populate it.
Input Format :
The first line contains an Integer 't' which
denotes the number of test cases or
queries to be run. Then the test cases follow.

The first and the only line of each test case
or query contains an integer 'N'.
*/
#include <iostream>
using namespace std;

void arrange(int *arr, int n)
{
    int left = 0;
    int right = n - 1;
    int counter = 1;
    while (left <= right)
    {
        if (counter % 2 == 1)
        {
            arr[left] = counter;
            counter++;
            left++;
        }
        else
        {
            arr[right] = counter;
            counter++;
            right--;
        }
    }
}

int main()
{
    int t;
    cin >> t;
    while (t--)
    {
        int n;
        cin >> n;

        int *arr = new int[n];
        arrange(arr, n);
        for (int i = 0; i < n; i++)
        {
            cout << arr[i] << " ";
        }
        cout << endl;
        delete[] arr;
    }
}