Array Left Rotation

Array Interview Question

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Array Left Rotation

Hey guys i am providing the solutions for the question given in the Chapter one Arrays and String of the very famous book Cracking the coding interview. All these solutions are written by myself and checked for all the possible cases. Please take a look at them and help your self to solve your problems. If you have any query regarding the solutions or you want to ask something leave your comment and i will get back to you as soon as possible. Happy coding.

A left rotation operation on an array of size shifts each of the array's elements unit to the left. For example, if left rotations are performed on array , then the array would become .
Given an array of integers and a number, , perform left rotations on the array. Then print the updated array as a single line of space-separated integers.
Input Format
The first line contains two space-separated integers denoting the respective values of (the number of integers) and (the number of left rotations you must perform). The second line contains space-separated integers describing the respective elements of the array's initial state.
Constraints
Output Format
Print a single line of space-separated integers denoting the final state of the array after performing left rotations.
Sample Input
5 4
1 2 3 4 5
Sample Output
5 1 2 3 4
Explanation
When we perform left rotations, the array undergoes the following sequence of changes:
Thus, we print the array's final state as a single line of space-separated values, which is 5 1 2 3 4.

import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) throws IOException{
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String as[]  =br.readLine().split("\\s");
        int n = Integer.parseInt(as[0]);
        int r = Integer.parseInt(as[1]);
        int c;
        String ele[] = br.readLine().split("\\s");
        ArrayList <Integer> arr = new ArrayList <Integer> ();
        for(int i=0;i<n;i++)
            {
             c = Integer.parseInt(ele[i]);
            arr.add(c);
        }
        for(int j=0;j<r;j++)
            {
             c = arr.remove(0);
            arr.add(c);
        }
        ListIterator <Integer> itr = null;
        itr  = arr.listIterator();
        while(itr.hasNext()){
       System.out.print(itr.next()+" ");
        }
    }
}

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Try more and more problems that you find on string and arrays and try to develop an approach the will help you understand problems rather then learning the solution. Once you know how to approach the problem you will able to solve any problem related to strings and array. I wish best of luck to you for your future.