Java Program For Array Rotation using temp array

After rotating d positions to the left, the first d elements become the last d elements of the array

First store the elements from index d to N-1 into the temp array.

Then store the first d elements of the original array into the temp array.

Copy back the elements of the temp array into the original array

Illustration:

Suppose the give array is arr[] = [1, 2, 3, 4, 5, 6, 7], d = 2.

First Step:
=> Store the elements from 2nd index to the last.
=> temp[] = [3, 4, 5, 6, 7]

Second Step:
=> Now store the first 2 elements into the temp[] array.
=> temp[] = [3, 4, 5, 6, 7, 1, 2]

Third Steps:
=> Copy the elements of the temp[] array into the original array.
=> arr[] = temp[] So arr[] = [3, 4, 5, 6, 7, 1, 2]

Step-by-step approach:

Initialize a temporary array(temp[n]) of length same as the original array
Initialize an integer(k) to keep a track of the current index
Store the elements from the position d to n-1 in the temporary array
Now, store 0 to d-1 elements of the original array in the temporary array
Lastly, copy back the temporary array to the original array

Below is the implementation of the above approach :

Java

/*package whatever //do not write package name here */
 
import java.io.*;
 
class GFG {
 
 
// Function to rotate array
static void Rotate(int arr[], int d, int n)
{
    // Storing rotated version of array
    int temp[] = new int[n];
 
    // Keeping track of the current index
    // of temp[]
    int k = 0;
 
    // Storing the n - d elements of
    // array arr[] to the front of temp[]
    for (int i = d; i < n; i++) {
        temp[k] = arr[i];
        k++;
    }
 
    // Storing the first d elements of array arr[]
    // into temp
    for (int i = 0; i < d; i++) {
        temp[k] = arr[i];
        k++;
    }
 
    // Copying the elements of temp[] in arr[]
    // to get the final rotated array
    for (int i = 0; i < n; i++) {
        arr[i] = temp[i];
    }
}
 
// Function to print elements of array
static void PrintTheArray(int arr[], int n)
{
    for (int i = 0; i < n; i++) {
        System.out.print(arr[i]+" ");
    }
}
    public static void main (String[] args) {
        int arr[] = { 1, 2, 3, 4, 5, 6, 7 };
        int N = arr.length;
        int d = 2;
 
        // Function calling
        Rotate(arr, d, N);
        PrintTheArray(arr, N);
    }
}
 
// This code is contributed by ishankhandelwals.

Output

3 4 5 6 7 1 2

Time complexity: O(N)
Auxiliary Space: O(N)

Java Program For Array Rotation

Write a Java Program for a given array of integers arr[] of size N and an integer, the task is to rotate the array elements to the left by d positions.

Examples:

Input:
arr[] = {1, 2, 3, 4, 5, 6, 7}, d = 2
Output: 3 4 5 6 7 1 2

Input: arr[] = {3, 4, 5, 6, 7, 1, 2}, d=2
Output: 5 6 7 1 2 3 4

Java Program For Array Rotation using temp array

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Java Program For Array Rotation

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Java Program For Array Rotation using temp array

Java

Java Program For Array Rotation

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