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Java Exercises: Find the total number of continuous subarrays in a specified array of integers

Java Basic: Exercise-203 with Solution

Write a Java program to find the contiguous subarray of given length k which has the maximum average value of a given array of integers. Display the maximum average value.

Example:
Original Array: [4, 2, 3, 3, 7, 2, 4]
Value of k: 3
Maximum average value : 4.333333333333333

Pictorial Presentation:

Java Basic Exercises: Find the total number of continuous subarrays in a specified array of integers

Sample Solution:

Java Code:

import java.util.*;
public class Solution {
    public static void main(String[] args) {		
        int[] nums = {4,2,3,3,7,2,4};
		int k = 3;
		System.out.print("Original Array: "+Arrays.toString(nums));
		System.out.print("\nValue of k: "+k);
		System.out.print("\nMaximum average value: "+find_max_average(nums, k));       
    }     
  public static double find_max_average(int[] nums, int k) {
        int sum = 0;
        for (int i = 0; i < k; i++) {
            sum += nums[i];
        }
        int max_val = sum;
        
        for (int i = k; i < nums.length; i++) {
            sum = sum - nums[i - k] + nums[i];
            max_val = Math.max(max_val, sum);
        }
        return (double) max_val / k;
    }
}

Sample Output: 

Original Array: [4, 2, 3, 3, 7, 2, 4]
Value of k: 3
Maximum average value: 4.333333333333333

Flowchart:

Flowchart: Java exercises: Find the total number of continuous subarrays in a specified array of integers

Java Code Editor:

Company:  Google

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Java: Tips of the Day

Check if at least two out of three booleans are true:

Rather than writing:

if (someExpression) {
    return true;
} else {
    return false;
}

Write:

return someExpression;

As for the expression itself, something like this:

boolean atLeastTwo(boolean a, boolean b, boolean c) {
    return a ? (b || c) : (b && c);
}

or this (whichever you find easier to grasp):

boolean atLeastTwo(boolean a, boolean b, boolean c) {
    return a && (b || c) || (b && c);
}

Ref: https://bit.ly/2OYPQD7