Maximum Average subarray of k length in C++

April 12, 2023

Maximum Average Sub-array of K length

On this page we will discuss about Maximum Average sub-array of k length in C++ language . We have to Find out the maximum possible average value of sub-array of K length from given sequence of N integers, a[1], a[2], , , , a[N] of N length and a integer K integer.

Maximum Average Sub-array of K length in C++

In C++, maximum average subarray of k length pertains to a contiguous sub-array of length k in a given array of numbers, where the average (mean) of the k elements is the highest among all possible sub-arrays of length k in that array. In simpler words, it refers to the sub-array of k consecutive elements whose sum is the largest possible among all sub-arrays of k consecutive elements in the array, resulting in the highest average value.

For example,consider the array

[1, 12, -5, -6, 50, 3] and k=4.

The subarrays of length 4 are [1, 12, -5, -6], [12, -5, -6, 50], [-5, -6, 50, 3], and their averages are 0.5, 12.75, and 10.5 respectively. The maximum average subarray of length 4 in this case is [12, -5, -6, 50], whose average is 12.75.

Boyer-Moore’s Voting Algorithm

Majority Element in Array

Sort the array in Waveform

Segregate 0’s 1’s and 2’s in array

Size of sub-array with max sum

Algorithm:

Initialize max_sum with the sum of the first k elements of arr and max_end with k-1, which represent the sum and ending index of the first subarray of length k.
Loop through the input array arr from index k to n-1 and for each index i, compute the sum of the subarray of length k ending at index i, i.e., curr_sum = sum of elements from arr[i-k+1] to arr[i].
Compare curr_sum with max_sum. If curr_sum is greater than max_sum, update max_sum with curr_sum and update max_end with the current index i.
After the loop, max_end will represent the ending index of the maximum average subarray of length k.
Return the starting index of the maximum average subarray of length k as max_end - k + 1.

C++ code for maximum average sub-array of k length

Run

#include<bits/stdc++.h>
using namespace std;
 
// Returns beginning index of maximum average
// subarray of length 'k'
int findMaxAverage(int arr[], int n, int k)
{
    // Check if 'k' is valid
    if (k > n)
        return -1;
 
    // Create and fill array to store cumulative
    // sum. csum[i] stores sum of arr[0] to arr[i]
    int *csum = new int[n];
    csum[0] = arr[0];
    for (int i=1; i max_sum)
        {
            max_sum = curr_sum;
            max_end = i;
        }
    }
 
    delete [] csum; // To avoid memory leak
 
    // Return starting index
    return max_end - k + 1;
}
 
// Driver program
int main()
{
    int arr[] = {-1, 10, -15, -6, 50, 3};
    int k = 4;
    int n = sizeof(arr)/sizeof(arr[0]);
    cout << "The maximum average subarray of "
         "length "<< k << " begins at index "
         << findMaxAverage(arr, n, k);
    return 0;
}

Output

The maximum average subarray of length 4 begins at index 1

Prime Course Trailer

Related Banners

Get PrepInsta Prime & get Access to all 200+ courses offered by PrepInsta in One Subscription

Get over 200+ course One Subscription

Courses like AI/ML, Cloud Computing, Ethical Hacking, C, C++, Java, Python, DSA (All Languages), Competitive Coding (All Languages), TCS, Infosys, Wipro, Amazon, DBMS, SQL and others

Checkout list of all the video courses in PrepInsta Prime Subscription

Introduction to Trees

Binary Trees

Binary Tree in Data Structures (Introduction)
Tree Traversals: Inorder Postorder Preorder : C | C++ | Java
Inorder Postorder PreOrder Traversals Examples
- Inorder Tree Traversal in Binary Tree: C | C++ | Java
- Preorder Tree Traversal in Binary Tree : C | C++ | Java
- Postorder Tree Traversal in Binary Tree : C | C++ | Java
Tree Traversal without Recursion
- Postorder Preorder Inorder Traversal without recursion
- Inorder Tree Traversal without Recursion – C | C++ | Java
- Preorder Tree Traversal without Recursion – C | C++ | Java
- Postorder Tree Traversal without Recursion – C | C++ | Java

Binary Search Trees

Binary search tree in Data Structures (Introduction)
- BST: Introduction to Binary Search Tree
- BST: Binary Search Tree Program : C | C++ | Java
- BST: Search a node in Binary Search Tree : C | C++ | Java
- BST: Insertion in a Binary Search Tree : C | C++ | Java
- BST: Deletion in a Binary Search Tree : C | C++ | Java

Traversals

Traversal in Trees
Tree Traversals: Breadth-First Search (BFS) : C | C++ | Java
Tree Traversals: Depth First Search (DFS) : C | C++ | Java
Construct a Binary Tree from Postorder and Inorder

B – Trees

B-Tree
- B-Tree: Introduction
- B-Tree: Insertion : C | C++ | Java
- B-Tree: Deletion : C | C++ | Java

AVL Trees

AVL Trees
- AVL Trees: Introduction
- AVL Tree Insertion : C | C++ | Java
- AVL Tree Deletion : C | C++ | Java
- Insertion in a Binary Tree (Level Order) – C | C++ | Java
- Searching in Binary Tree – C | C++ | Java
- Searching in a Binary Search Tree – C | C++ | Java

Complete Programs for Trees

Depth First Traversals – C | C++ | Java
Level Order Traversal – C | C++ | Java
Construct Tree from given Inorder and Preorder traversals – C | C++ | Java
Construct Tree from given Postorder and Inorder traversals – C | C++ | Java
Construct Tree from given Postorder and Preorder traversal – C | C++ | Java
Find size of the Binary tree – C | C++ | Java
Find the height of binary tree – C | C++ | Java
Find maximum in binary tree – C | C++ | Java
Check whether two tree are identical- C| C++| Java
Spiral Order traversal of Tree- C | C++| Java
Level Order Traversal Line by Line – C | C++| Java
Hand shaking lemma and some Impotant Tree Properties.
Check If binary tree if Foldable or not.- C| C++| Java
check whether tree is Symmetric – C| C++| Java.
Check for Children-Sum in Binary Tree- C|C++| Java
Sum of all nodes in Binary Tree- C | C++ | Java
Lowest Common Ancestor in Binary Tree- C | C++ | Java