Java: Test if an array of integers contains an element 10 next to 10 or an element 20 next to 20, but not both

Last update on April 01 2025 10:51:05 (UTC/GMT +8 hours)

Check Adjacent 10s or 20s

Write a Java program to test if an array of integers contains an element 10 next to 10 or an element 20 next to 20, but not both.

Sample Solution:

Java Code:

import java.util.*;
public class Exercise93 {
    public static void main(String[] args) {
        // Define an array of integers
        int[] nums = {10, 10, 2, 4, 20, 20};
        
        // Initialize counters for even and odd numbers
        int ctr_even = 0, ctr_odd = 0;
        
        // Display the original array
        System.out.println("Original Array: " + Arrays.toString(nums));

        // Initialize boolean variables to check for specific patterns
        boolean found1010 = false;
        boolean found2020 = false;
        
        // Iterate through the array to find patterns (e.g., 1010 and 2020)
        for (int i = 0; i < nums.length - 1; i++) {
            if (nums[i] == 10 && nums[i + 1] == 10) {
                found1010 = true;
            }

            if (nums[i] == 20 && nums[i + 1] == 20) {
                found2020 = true;
            }
        }

        // Check if the patterns 1010 and 2020 were found and print the result
        System.out.printf(String.valueOf(found1010 != found2020));
        System.out.printf("\n");
    }
}

Sample Output:

Original Array: [10, 10, 2, 4, 20, 20]                                 
false 

Pictorial Presentation:

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to check if an array contains two adjacent 5s or two adjacent 15s, but not both.
• Write a Java program to check if a specified number appears at least twice in an array but never consecutively.
• Write a Java program to check if an array contains a 30 adjacent to 30 or a 40 adjacent to 40, but not both.
• Write a Java program to find the longest sequence of consecutive identical numbers in an array.

Java Code Editor:

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