Introduction
Finding the sum of all elements in an array is a basic operation that is commonly used in various programming tasks. This guide will walk you through writing a Java program that calculates the sum of the elements in a given array.
Problem Statement
Create a Java program that:
- Prompts the user to enter the size of an array and its elements.
- Calculates the sum of all the elements in the array.
- Displays the sum.
Example:
- Input:
[1, 2, 3, 4, 5]
- Output:
"Sum of elements: 15"
Solution Steps
- Read the Array Size and Elements: Use the
Scanner
class to take the size and elements of the array as input from the user. - Initialize a Sum Variable: Initialize a variable to store the sum of the elements.
- Traverse the Array: Use a loop to iterate through the array and accumulate the sum of its elements.
- Display the Result: Print the sum of the elements.
Java Program
// Java Program to Find the Sum of Elements in an Array // Author: https://www.rameshfadatare.com/ import java.util.Scanner; public class SumOfArrayElements { public static void main(String[] args) { // Step 1: Read the size and elements of the array from the user Scanner scanner = new Scanner(System.in); System.out.print("Enter the size of the array: "); int size = scanner.nextInt(); int[] array = new int[size]; System.out.println("Enter the elements of the array:"); for (int i = 0; i < size; i++) { array[i] = scanner.nextInt(); } // Step 2: Initialize sum variable int sum = 0; // Step 3: Traverse the array and calculate the sum for (int i = 0; i < size; i++) { sum += array[i]; } // Step 4: Display the sum of elements System.out.println("Sum of elements: " + sum); } }
Explanation
Step 1: Read the Array Size and Elements
- The
Scanner
class is used to read the size of the array and its elements. ThenextInt()
method captures the size and each element.
Step 2: Initialize a Sum Variable
- A variable
sum
is initialized to0
. This variable will be used to accumulate the sum of the array elements.
Step 3: Traverse the Array
- A
for
loop is used to iterate through each element of the array. - During each iteration, the value of the current element is added to
sum
.
Step 4: Display the Result
- The program prints the total sum of the elements using
System.out.println()
.
Output Example
Example 1:
Enter the size of the array: 5 Enter the elements of the array: 1 2 3 4 5 Sum of elements: 15
Example 2:
Enter the size of the array: 3 Enter the elements of the array: 10 20 30 Sum of elements: 60
Example 3:
Enter the size of the array: 6 Enter the elements of the array: 5 10 15 20 25 30 Sum of elements: 105
Conclusion
This Java program demonstrates how to calculate the sum of elements in an array. It covers basic concepts such as loops, array traversal, and arithmetic operations, making it a valuable exercise for beginners learning Java programming.