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Left Rotation in an Array using Java

Left Rotation in an Array using Java

There are two methods implemented by me here :-

1) Using extra Array 
  1.  Get new position of  a current element using formula.
  2.  Add the element in the new position in a new array.

2) Using same Array:- This is little bit complex

  1. hold variable at index i.
  2. find new index for variable.
  3. hold variable present at new index.
  4. place variable at index i to this new index.
  5. assign i to new index variable.
  6. repeat steps until count is not equal to lenght of an array which simply means all variable got covered.

package Arrays;

 * 12345 to 34512

 * sample input
 * 5 4(d=4 that is 4 rotations)
 1 2 3 4 5
 sample output
public class LeftRotation {
 public static void printArray(int[] arr)
  for(int i=0;i<arr.length;i++)
  System.out.print(" "+arr[i]);
  System.out.println(" ");
 //method which returns rotated array using extra array
 public static int[] leftRotate(int[] arr, int rotation)
  int temparr[]=new int[arr.length];
  int pos;
  for(int i=0;i<arr.length;i++)
  return temparr;

 //method which returns rotated array using same array
 public static int[] leftRotate2(int[] arr, int rotation)
  int pos,tempinit,temppos=arr[0],i=0,c=0;
  return arr;

 public static void main(String[] args)
  int[] arr={1,2,3,4,5};
  leftRotate(arr, 3);
  leftRotate2(arr, 3);



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