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Recap - All About Arrays

Part of the Logic & Flow section of Coddy's Java journey — lesson 9 of 59.

Challenge

Easy

Create a method named arrayOperations that takes a 2D array of integers (matrix) as input and performs the following operations:

Calculate the sum of all elements in the matrix.
Find the maximum element in the matrix.
Create a new 1D array that contains the sums of each row in the matrix.
Print to the console using the following format:

Sum: 78
Maximum: 12
Row Sums: [10, 26, 42]

Try it yourself

import java.util.Arrays;

// Write your code only inside the class. Do not write main() or any code outside this class.
class ArrayOperations {
    public static void arrayOperations(int[][] matrix) {
        // Write your code here
    
    
        System.out.println("Sum: " + sum);
        System.out.println("Maximum: " + max);
        System.out.println("Row Sums: " + Arrays.toString(rowSums));

    }
}

All lessons in Logic & Flow

1Multi-dimensional Arrays

2D Arrays Basics Accessing 2D Array Elements Nested Loops with 2D Arrays Recap - 2D Arrays Matrix Addition & Substraction Jagged Arrays 3D Arrays And Beyond Common 2D Array PatternsRecap - All About Arrays

4HashSet Part 1

What is a HashSet?Adding an Element Removing an Element Checking if an Element Exists Empty and Size Clear and Clone Recap - HashSet

7Basic Error Handling

Try-Catch Basics Finally Block Throwing Exceptions Custom Exceptions

10Date and Time

LocalDate Basics LocalTime Operations LocalDateTime Usage Period and Duration Date Formatting Time Zone Handling

2HashMap Part 1

What is a HashMap?Declare a HashMap Accessing Values Check If Key Exists Modifying Dictionaries Recap - HashMap

5HashSet Part 2

Math - Union of HashSets Math - Intersection of HashSet Math - Set Difference Math - Symmetric Difference Subsets and Supersets Iterating Over Sets

8Advanced String Operations

StringBuilder Basics StringBuffer Introduction Regular Expressions Basics Pattern Matching with Regex String Tokenizer Advanced String Formatting

3HashMap Part 2

HashMap Methods Iterate with keySet()Iterate with entrySet()Nested HashMap Recap - Manage Warehouse Recap - HashMap Operations

6Advanced Control Flow

Label Statements Switch Expression Pattern Matching Guard Clauses Recap - Control Flow

9Project - Unique Word Counter

Text Input and Storage Word Processing

Project lesson

Project lesson

Advanced Statistics

Project lesson