Print left rotation of array in O(n) time and O(1) space

Given an array of size n and multiple values around which we need to left rotate the array. How to quickly print multiple left rotations?

Examples :

Input : arr[] = {1, 3, 5, 7, 9}
        k1 = 1
        k2 = 3
        k3 = 4
        k4 = 6
Output : 3 5 7 9 1
         7 9 1 3 5
         9 1 3 5 7
         3 5 7 9 1

Input : arr[] = {1, 3, 5, 7, 9}
        k1 = 14 
Output : 9 1 3 5 7

Recommended: Please solve it on “PRACTICE ” first, before moving on to the solution.

We have discussed a solution in below post.
Quickly find multiple left rotations of an array | Set 1

The solution discussed above requires extra space. In this post, an optimized solution is discussed that doesn’t require extra space.

C++

// CPP implementation of left rotation of 
// an array K number of times 
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to leftRotate array multiple times 
void leftRotate(int arr[], int n, int k) 
{ 
    /* To get the starting point of rotated array */
    int mod = k % n; 
  
    // Prints the rotated array from start position 
    for (int i = 0; i < n; i++) 
        cout << (arr[(mod + i) % n]) << " "; 
  
    cout << "\n"; 
} 
  
// Driver program 
int main() 
{ 
    int arr[] = { 1, 3, 5, 7, 9 }; 
    int n = sizeof(arr) / sizeof(arr[0]); 
  
    int k = 2; 
    leftRotate(arr, n, k); 
  
    k = 3; 
    leftRotate(arr, n, k); 
  
    k = 4; 
    leftRotate(arr, n, k); 
  
    return 0; 
} 

Java

// JAVA implementation of left rotation 
// of an array K number of times 
import java.util.*; 
import java.lang.*; 
import java.io.*; 
  
class arr_rot 
{    
    // Function to leftRotate array multiple 
    // times 
    static void leftRotate(int arr[], int n, 
                                     int k) 
    { 
        /* To get the starting point of  
        rotated array */
        int mod = k % n; 
      
        // Prints the rotated array from  
        // start position 
        for(int i = 0; i < n; ++i) 
        System.out.print(arr[(i + mod) % n] 
                          + " ");  
          
        System.out.println(); 
    } 
      
    // Driver program 
    public static void main (String[] args)  
    { 
            int arr[] = { 1, 3, 5, 7, 9 }; 
            int n = arr.length;  
  
            int k = 2; 
            leftRotate(arr, n, k); 
  
            k = 3; 
            leftRotate(arr, n, k); 
  
            k = 4; 
            leftRotate(arr, n, k); 
    } 
} 
  
// This code is contributed by Sanjal 

Python

# Python implementation of left rotation of 
# an array K number of times 
  
# Function to leftRotate array multiple times 
def leftRotate(arr, n, k): 
  
    # To get the starting point of rotated array 
    mod = k % n 
    s = "" 
  
    # Prints the rotated array from start position 
    for i in range(n): 
        print str(arr[(mod + i) % n]), 
    print
    return
  
# Driver program 
arr = [ 1, 3, 5, 7, 9 ] 
n = len(arr) 
k = 2
leftRotate(arr, n, k) 
  
k = 3
leftRotate(arr, n, k) 
  
k = 4
leftRotate(arr, n, k) 
  
#This code is contributed by Sachin Bisht 

C#

// C# implementation of left 
// rotation of an array K 
// number of times 
using System; 
  
class GFG 
{ 
      
    // Function to leftRotate  
    // array multiple times 
    static void leftRotate(int []arr,  
                           int n, int k) 
    { 
        // To get the starting   
        // point of rotated array  
        int mod = k % n; 
      
        // Prints the rotated array   
        // from start position 
        for(int i = 0; i < n; ++i) 
        Console.Write(arr[(i + mod) %  
                           n] + " ");  
          
        Console.WriteLine(); 
    } 
      
    // Driver Code 
    static public void Main () 
    { 
        int []arr = {1, 3, 5, 7, 9}; 
        int n = arr.Length;  
      
        int k = 2; 
        leftRotate(arr, n, k); 
      
        k = 3; 
        leftRotate(arr, n, k); 
      
        k = 4; 
        leftRotate(arr, n, k); 
    } 
} 
  
// This code is contributed by m_kit 

PHP

<?php 
// PHP implementation of  
// left rotation of an 
// array K number of times 
  
// Function to leftRotate 
// array multiple times 
function leftRotate($arr, $n, $k) 
{ 
    // To get the starting 
    // point of rotated array 
    $mod = $k % $n; 
  
    // Prints the rotated array 
    // from start position 
    for ($i = 0; $i < $n; $i++) 
        echo ($arr[($mod +  
                    $i) % $n]) , " "; 
  
    echo "\n"; 
} 
  
// Driver Code 
$arr = array(1, 3, 5, 7, 9); 
$n = sizeof($arr); 
  
$k = 2; 
leftRotate($arr, $n, $k); 
  
$k = 3; 
leftRotate($arr, $n, $k); 
  
$k = 4; 
leftRotate($arr, $n, $k); 
  
// This code is contributed by m_kit 
?> 

Output :

5 7 9 1 3 
7 9 1 3 5 
9 1 3 5 7

This article is contributed by Sridhar Babu. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.

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My Personal Notes

Recommended: Please solve it on “PRACTICE ” first, before moving on to the solution.

C++

Java

Python

C#

PHP

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