# Left Rotation

### Problem Statement :

```A left rotation operation on an array of size n shifts each of the array's elements 1 unit to the left. Given an integer, d, rotate the array that many steps left and return the result.

Example:
d=2
arr=[1,2,3,4,5]

After 2 rotations, arr'=[3,4,5,1,2].

Function Description:

Complete the rotateLeft function in the editor below.

rotateLeft has the following parameters:
1. int d: the amount to rotate by
2. int arr[n]: the array to rotate

Returns
1. int[n]: the rotated array

Input Format:

The first line contains two space-separated integers that denote n, the number of integers, and d, the number of left rotations to perform.
The second line contains n space-separated integers that describe arr[].

Constraints:
1. 1<=n<=10^5
2. 1<=d<=n
3. 1<=a[i]<=10^6```

### Solution :

```                            ```Solution in C :

In C:

#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

int main() {

int N;
int d;
scanf("%d %d", &N, &d);
int A[N];
for (int i = 0; i < N; i++)
{
scanf("%d", &A[i]);
}
for (int i = 0; i < N; i++)
{
printf("%d ", A[(i + d) % N]);
}
puts("");

return 0;
}

In C++:

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

int main() {
int N, d, i;
cin >> N >> d;
int start = N - d;
int *arr = new int[N];
for (i=0; i<N; ++i) {
if (start == N) start = 0;
cin >> arr[start++];
}
for (i=0; i<N; ++i) cout << arr[i] << " ";
return 0;
}

In Java:

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

public class Solution {

public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
int N = scan.nextInt();
int n = scan.nextInt();
int[] A = new int[N];
for (int i=0; i<N; ++i) {
A[i] = scan.nextInt();
}
for (int i=0; i<n; ++i) {
rotateArray(A);
}
for (int a : A) {
System.out.print(a+" ");
}
System.out.println("");
}

private static void rotateArray(int[] A) {
int t = A[0];
for (int i=0; i<A.length-1; ++i) {
A[i] = A[i+1];
}
A[A.length-1] = t;
}
}

In Python 3:

n, d = map(int, input().split())
arr = [int(x) for x in input().split()]

for i in range(d):
arr.append(arr[i])

for x in arr[d:]:
print(x, end=' ')```
```

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