Copy And Reverse The Array

Easy
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Average time to solve is 10m
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CognizantAmdocsEncore Capital Group

Problem statement

You are given an array 'ARR' consisting of 'N' non-negative integers, your task is to copy the elements of 'ARR' into another array 'COPY_ARR' in reverse order.

For example:

If 'ARR' contains the following elements [ 1, 2, 3, 4, 5 ], then you should return another array that is equal to [ 5, 4, 3, 2, 1].
Detailed explanation ( Input/output format, Notes, Images )
Input Format :
The first line of the input contains a single integer T, denoting the number of test cases.

The first line of each test case contains a single integer N, denoting the length of the array 'ARR'.

The second line of each test case contains N space-separated integers, denoting the elements of the array.
Output Format :
For each test case print, N space-separated integers, where the ith integer denotes the ith element of the array 'COPY_ARR'.
Note:
You do not need to print anything. It has already been taken care of. Just implement the given function.
Constraints :
1 <= T <= 10^2
1 <= N <= 10^4
0 <= ARR[i] <= 10^9

Time Limit: 1 sec
Sample Input 1 :
2
5
1 2 3 4 5
4
5 8 2 1
Sample Output 1 :
5 4 3 2 1
1 2 8 5
Explanation For Sample Input 1 :
The reverse of [1, 2, 3, 4, 5] is [5, 4, 3, 2,1]
The reverse of [5, 8, 2, 1] is [1, 2, 8, 5].
Sample Input 2 :
3
3
3 2 1
4
8  6 2 4
5
1 3 5 4 2
Sample Output 2 :
1 2 3
4 2 6 8
2 4 5 3 1
Explanation For Sample Input 2 :
The reverse of [3, 2, 1] is [1, 2, 3].
The reverse of [8, 6, 2, 4] is [4, 2, 6, 8].
The reverse of [1, 3, 5, 4, 2] is [2, 4, 5, 3, 1].
Hint

Try to go from end to beginning in the ARR.

Approaches (1)
Array Traversal
  1. Declare a new array COPY_ARR of length equal to that of ARR, let the length be N.
  2. Iterate the array ARR and copy the value at ith position in ARR to N-i-1 th position in COPY_ARR. That is COPY_ARR[N-i-1] = ARR[i]
Time Complexity

O(N) , where N is the length of the array ARR.

 

The time complexity is O(N) because we are traversing the complete array of N elements

Space Complexity

O(1).

 

 As we are using constant extra memory.

Code Solution
(100% EXP penalty)
Copy And Reverse The Array
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