Added full code of maximum average of subarray

Author: ujjawalsinghsde

Code Practice/Maximum average subarray/Readme.md

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+## Maximum average subarray
+Given an array Arr of size N and a positive integer K, find the sub-array of length K with the maximum average. [🔗Goto](https://practice.geeksforgeeks.org/problems/maximum-average-subarray5859/1#) 
+
+```
+Example 1:
+
+Input:
+K = 4, N = 6
+Arr[] = {1, 12, -5, -6, 50, 3}
+Output: 12 -5 -6 50
+Explanation: Maximum average is 
+(12 - 5 - 6 + 50)/4 = 51/4.
+
+Example 2:
+
+Input:
+K = 3, N = 7
+Arr[] = {3, -435, 335, 10, -50, 100, 20}
+Output: 335 10 -50
+Explanation: Maximum average is 
+(335 + 10 - 50)/3 = 295/3.
+```
+<details>
+<summary>Full Code</summary>
+
+```java
+import java.io.*;
+import java.util.*;
+
+public class GFG {
+    public static void main(String[] args) throws Exception {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int tc = Integer.parseInt(br.readLine().trim());
+        while (tc-- > 0) {
+            String[] inputLine;
+            inputLine = br.readLine().trim().split(" ");
+            int k = Integer.parseInt(inputLine[0]);
+            inputLine = br.readLine().trim().split(" ");
+            int n = Integer.parseInt(inputLine[0]);
+            int[] arr = new int[n];
+            inputLine = br.readLine().trim().split(" ");
+            for (int i = 0; i < n; i++) {
+                arr[i] = Integer.parseInt(inputLine[i]);
+            }
+
+            int ans = new Solution().findMaxAverage(arr, n, k);
+            for(int i=ans; i<ans+k; i++)
+                System.out.print(arr[i]+" ");
+            System.out.println();
+        }
+    }
+}
+// } Driver Code Ends
+
+
+//User function Template for Java
+
+class Solution {
+    int findMaxAverage(int[] arr, int n, int k) {
+         if (k > n) return -1;
+
+        // Compute sum of first 'k' elements
+        int sum = arr[0];
+        for (int i = 1; i < k; i++) 
+            sum += arr[i];
+
+        int max_sum = sum, max_end = k - 1;
+
+        // Compute sum of remaining subarrays
+        for (int i = k; i < n; i++) {
+            sum = sum + arr[i] - arr[i - k];
+            if (sum > max_sum) {
+                max_sum = sum;
+                max_end = i;
+            }
+        }
+        // Return starting index
+        return max_end - k + 1;
+    }
+}
+
+```
+</details>
+
+```java
+class Solution {
+    int findMaxAverage(int[] arr, int n, int k) {
+         if (k > n) return -1;
+
+        // Compute sum of first 'k' elements
+        int sum = arr[0];
+        for (int i = 1; i < k; i++) 
+            sum += arr[i];
+
+        int max_sum = sum, max_end = k - 1;
+
+        // Compute sum of remaining subarrays
+        for (int i = k; i < n; i++) {
+            sum = sum + arr[i] - arr[i - k];
+            if (sum > max_sum) {
+                max_sum = sum;
+                max_end = i;
+            }
+        }
+        // Return starting index
+        return max_end - k + 1;
+    }
+}
+```