How to Rotate Elements in an Array in C - Step by Step Examples

How to Rotate Elements in an Array in C ?

Answer

To rotate elements in an array in C, you can use a temporary array or perform the rotation in place using loops. The rotation can be either to the left or to the right, depending on your requirements.

✐ Examples

1 Rotate Array to the Left

In this example,

We create an array named arr with integer values.
We define a variable n to specify the number of elements in the array and a variable k to specify the number of positions to rotate.
We create a temporary array to store the elements after rotation.
We use a loop to copy the elements to the temporary array in their new positions.
Finally, we copy the elements from the temporary array back to the original array and print the rotated array.

C Program

#include <stdio.h>

void rotateLeft(int arr[], int n, int k) {
    int temp[n];
    for (int i = 0; i < n; i++) {
        temp[i] = arr[(i + k) % n];
    }
    for (int i = 0; i < n; i++) {
        arr[i] = temp[i];
    }
}

int main() {
    int arr[] = {1, 2, 3, 4, 5};
    int n = sizeof(arr) / sizeof(arr[0]);
    int k = 2; // Number of positions to rotate
    rotateLeft(arr, n, k);
    printf("Rotated array: ");
    for (int i = 0; i < n; i++) {
        printf("%d ", arr[i]);
    }
    return 0;
}

Output

Rotated array: 3 4 5 1 2

2 Rotate Array to the Right

In this example,

We create an array named arr with integer values.
We define a variable n to specify the number of elements in the array and a variable k to specify the number of positions to rotate.
We create a temporary array to store the elements after rotation.
We use a loop to copy the elements to the temporary array in their new positions.
Finally, we copy the elements from the temporary array back to the original array and print the rotated array.

C Program

#include <stdio.h>

void rotateRight(int arr[], int n, int k) {
    int temp[n];
    for (int i = 0; i < n; i++) {
        temp[(i + k) % n] = arr[i];
    }
    for (int i = 0; i < n; i++) {
        arr[i] = temp[i];
    }
}

int main() {
    int arr[] = {1, 2, 3, 4, 5};
    int n = sizeof(arr) / sizeof(arr[0]);
    int k = 2; // Number of positions to rotate
    rotateRight(arr, n, k);
    printf("Rotated array: ");
    for (int i = 0; i < n; i++) {
        printf("%d ", arr[i]);
    }
    return 0;
}

Output

Rotated array: 4 5 1 2 3

Summary

In this tutorial, we learned How to Rotate Elements in an Array in C language with well detailed examples.

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