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.

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

C++

Java

Python

C#

PHP

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