Data structures are the backbone of efficient programming! They help organize and store data in ways that make problem-solving faster and more effective. Betinexchange247

With out extra space , use reverse function

vector<int> rotateLeft(int d, vector<int> arr) {
    int n = arr.size();
    d = n - d%n;
    if(d==n) return arr;
    reverse(arr.begin(), arr.end());
    reverse(arr.begin(), arr.begin()+d);
    reverse(arr.begin()+d, arr.end());
    return arr;
}

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

public class Solution {

public static void main(String[] args) {
    Scanner in = new Scanner(System.in);

    int n = in.nextInt();  // number of elements
    int d = in.nextInt();  // number of left rotations

    int[] arr = new int[n];
    for (int i = 0; i < n; i++) {
        arr[i] = in.nextInt();
    }

    // Perform left rotations efficiently
    int[] rotated = new int[n];
    for (int i = 0; i < n; i++) {
        rotated[i] = arr[(i + d) % n];
    }

    // Print result
    for (int i = 0; i < n; i++) {
        System.out.print(rotated[i] + (i < n - 1 ? " " : ""));
    }

    in.close();
}

}

Here's a solution in Javascript

function rotateLeft(d, arr) {
  let arrSlice = arr.slice(0, d);
  let rotateArr = arr.slice(d)
  let finalArr = [...rotateArr, ...arrSlice];
  return finalArr;
}

Simple solution in JS (not pure though:))

function rotateLeft(d, arr) {
    // Write your code here
    while(d--) {
        arr.push(arr.shift());
    }
    
    return arr;
}