 # Python Program to right rotate elements of array

October 17, 2021, Learn eTutorial
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## How to right rotate or shift elements in an array?

In this python program, we need to right-rotate the array. An array is a collection of elements of the same data type which is stored in sequential memory locations. We have to move each element n number of times to the right, where the n is given by the user.

For example, consider an array A with 5 elements: A = [ 1, 2, 3, 4, 5]. Suppose we have the value for n is 2, then we have to shift 2 times to the right.

• In the first iteration, we will shift by one to right and append the last element of the array to the array's first position, and A will be like A = [ 5, 1, 2, 3, 4]
• In the second iteration, we will shift again to the right once more and then append the last one to the first of the array. Then it will then be like A = [ 4, 5, 1, 2, 3]

## How to implement the array elements right shift in Python?

So applying this logic in the python program, we use nested `for loop` in python. One outer `for loop`, which loops from zero to the value of n and assigns the variable last with the array's last element. Outer `for loop` is continued till how many times the user wants to rotate the elements to the right. Now we use the inner `for loop` in the reverse direction, which means, from the last element of the array minus one to zero decrementing by one and applying array[j] = array[j-1]. Then finally we append the value in last as the first element.

### ALGORITHM

STEP 1: initialize an array with some predefined values in it.

STEP 2: Add value to n to determine how many times we have to right-shift the array elements.

STEP 3: Display the real array using the `for loop` and `print` statement in the python programming language.

STEP 4: Add the outer `for loop` from zero to n and apply a variable last with the value of the last element of the array.

STEP 5: Use the inner `for loop` from the end of the array minus one to zero decrementing one.

STEP 6: Assign the value of array[j] = arr[j-1] and append the first element from the variable last.

STEP 7: Display the array after the right shift using `for loop` in python.

To rotate the array elements in python, we need to use the below concepts, We recommend to learn those for better understanding

## Python Source Code

```                                          ```arr = [1, 2, 3, 4, 5];

n = 3;    # value of how many times the array should be right shifted

print("Original array: ");    # display the real array
for i in range(0, len(arr)):
print(arr[i])

for i in range(0, n):

last = arr[len(arr)-1];    # add the last element of array to a variable

for j in range(len(arr)-1, -1, -1):

arr[j] = arr[j-1];    # use the for loop and assign the value array[j] = array[j-1]

arr = last;    # append the first element of array from the variable

print("\nArray after right rotation: ");    # print array after rotation
for i in range(0, len(arr)):
print(arr[i])  ```
```

## OUTPUT

```Original array:
1
2
3
4
5

Array after right rotation:
3
4
5
1
2
```

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