Added array left rotation solution in ds category

Author: kanahaiya

HackerRankDashboard/CoreCS/DataStructures/src/main/java/com/javaaid/hackerrank/solutions/datastructures/arrays/LeftRotation.java

@@ -0,0 +1,46 @@
+/**
+ * 
+ * Problem Statement-
+ * [Arrays: Left Rotation](https://www.hackerrank.com/challenges/ctci-array-left-rotation/problem)
+ * [Tutorial](https://youtu.be/TurKRD6Ne6w)
+ */
+package com.javaaid.hackerrank.solutions.datastructures.arrays;
+
+import java.util.Arrays;
+import java.util.Scanner;
+
+/**
+ * @author Kanahaiya Gupta
+ *
+ */
+public class LeftRotation {
+
+	static int[] rotLeft(int[] a, int d) {
+		int n = a.length;
+		int[] rotArray = new int[n];
+
+		for (int oldIndex = 0; oldIndex < n; oldIndex++) {
+			int newIndex = (oldIndex + n - d) % n;
+			rotArray[newIndex] = a[oldIndex];
+		}
+
+		return rotArray;
+
+	}
+
+	public static void main(String[] args) {
+
+		Scanner sc = new Scanner(System.in);
+		int arraySize = sc.nextInt();
+		int d = sc.nextInt();
+		int a[] = new int[arraySize];
+		for (int i = 0; i < a.length; i++) {
+			a[i] = sc.nextInt();
+		}
+
+		int res[] = rotLeft(a, d);
+		System.out.println(Arrays.toString(res));
+		sc.close();
+	}
+
+}