Cyclically Rotate An Array By One

Easy

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Average time to solve is 10m

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Problem statement

You are given an integer array of size N. Your task is to rotate the array by one position in the clockwise direction.

For example :

If N = 5 and arr[ ] = {1, 2, 3, 4, 5} then output will be 5 1 2 3 4.

If N = 8 and arr[ ] = {9, 8, 7, 6, 4, 2, 1, 3} then output will be 3 9 8 7 6 4 2 1.

Detailed explanation ( Input/output format, Notes, Images )

Input format :

The first line of input contains an integer ‘T’ denoting the number of test cases.
Then the T test cases follow.

The first line of each test case contains an integer ‘N’, the length of the array.

The second line of each test case contains N space-separated integers denoting the elements of the array.

Output format :

For each test case, printed the rotated array.

Note :

You do not need to print anything; it has already been taken care of. Just implement the given functions.

Constraints :

1 <= T <= 5
1 <= N <= 1000
-10^9 <= arr[i] <=10^9

Sample Input 1 :

1
5
1 2 3 4 5

Sample Output 1 :

5 1 2 3 4

Explanation For Sample Input 1 :

The first four elements are shifted towards the right by one position, and the last element i.e. 5 is shifted to the first position.

Sample Input 2 :

1
8
9 8 7 6 4 2 1 3

Sample Output 2 :

3 9 8 7 6 4 2 1

Hint 1

Think about shifting the elements of the array one position ahead.

Approaches (1)

Approach 1

Brute-Force

In this approach, we will first store the last element of the array in a variable let's say ‘x’. Now, shift all the elements one position to the right-hand side or in a clockwise direction. Finally, replace the first element of the array with ‘x’.

Algorithm:

Store the last element of the array in a variable say x.
Shift all elements one position to the right-hand side (clockwise rotation).
Replace the first element of the array with x.

Time Complexity

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

As we are traversing the array only once.

Space Complexity

O(1)

Constant extra space is required.

(100% EXP penalty)

Cyclically Rotate An Array By One

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