In this HackerRank Arrays: Left Rotation interview preparation kit problem you have Given an array a of n integers and a number, d, perform d left rotations on the array. Return the updated array to be printed as a single line of space-separated integers.


HackerRank Arrays: Left Rotation Interview Preparation kit solution


Problem solution in Python programming.

#!/bin/python3

import math
import os
import random
import re
import sys

# Complete the rotLeft function below.
def rotLeft(a, d):
    a = list(a)
    return a[d:] + a[:d]

if __name__ == '__main__':
    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    nd = input().split()

    n = int(nd[0])

    d = int(nd[1])

    a = list(map(int, input().rstrip().split()))

    result = rotLeft(a, d)

    fptr.write(' '.join(map(str, result)))
    fptr.write('\n')

    fptr.close()


Problem solution in Java Programming.

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    // Complete the rotLeft function below.
    static int[] rotLeft(int[] a, int d) {
        int length = a.length;
        int j = 0;
        int[] temp = new int[length];
        
        for(int i = d; i < length; i++, j++) {
            temp[j] = a[i];
        } 
        if(j < length) {
             for(int i = 0; i < d; i++, j++) {
                 temp[j] = a[i];
             }
        }
       
        return temp;
    }
    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) throws IOException {
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        String[] nd = scanner.nextLine().split(" ");

        int n = Integer.parseInt(nd[0]);

        int d = Integer.parseInt(nd[1]);

        int[] a = new int[n];

        String[] aItems = scanner.nextLine().split(" ");
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

        for (int i = 0; i < n; i++) {
            int aItem = Integer.parseInt(aItems[i]);
            a[i] = aItem;
        }

        int[] result = rotLeft(a, d);

        for (int i = 0; i < result.length; i++) {
            bufferedWriter.write(String.valueOf(result[i]));

            if (i != result.length - 1) {
                bufferedWriter.write(" ");
            }
        }

        bufferedWriter.newLine();

        bufferedWriter.close();

        scanner.close();
    }
}


Problem solution in C++ programming.

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <unordered_map>

using namespace std;

vector<int> array_left_rotation(vector<int> a, int n, int k) {
    vector<int> output(n);
    for (int i = 0; i < n; i++)
        {
            output[(i - k +n)%n] = a[i];
        }
    
    return output;
}
int main(){
    int n;
    int k;
    cin >> n >> k;
    vector<int> a(n);
    for(int a_i = 0;a_i < n;a_i++){
        cin >> a[a_i];
    }
    vector<int> output = array_left_rotation(a, n, k);
    for(int i = 0; i < n;i++)
        cout << output[i] << " ";
    cout << endl;
    return 0;
}


Problem solution in C programming.

#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int main(){
    int n; 
    int k;
    
    int i, j;
    
    scanf("%d %d",&n,&k);
    int *a = malloc(sizeof(int) * n);
    int *b = malloc(sizeof(int) * n);
    for(int a_i = 0; a_i < n; a_i++){
       scanf("%d",&b[a_i]);
    }

    for(i=0; i<n; i++){
       j = ((i - k)% n + n) % n;
       a[j] = b[i] ;    
    }
    for(i=0; i<n; i++){
       printf("%d ", a[i]);
    }
    
    free(a);
    free(b);
    
    return 0;
}


Problem solution in JavaScript programming.

process.stdin.resume();
process.stdin.setEncoding('ascii');

var input_stdin = "";
var input_stdin_array = "";
var input_currentline = 0;

process.stdin.on('data', function (data) {
    input_stdin += data;
});

process.stdin.on('end', function () {
    input_stdin_array = input_stdin.split("\n");
    main();    
});

function readLine() {
    return input_stdin_array[input_currentline++];
}

/////////////// ignore above this line ////////////////////

function main() {
    var n_temp = readLine().split(' ');
    var n = parseInt(n_temp[0]);
    var k = parseInt(n_temp[1]);
    a = readLine().split(' ');
    a = a.map(Number);
    console.log(a.slice(k).concat(a.slice(0, k)).join(' '));
}