Java Programming for SDET Interview Coding Challenges

Implement a Java program that reads a number with a scanner, sums its digits using a while loop with modulus and division by ten, and prints the result.

Learn to write a Java program that uses a scanner to read three numbers and determine the largest using an if-else comparison, with clear step-by-step input and output.

Learn to check if an integer is prime in Java using a scanner for input and an isPrime method; test divisibility up to the square root and print the result.

Take an input string, count the frequency of each character, then sort characters by frequency in descending order using bubble sort, and print each character with its frequency.

Create a Java program that counts vowels in a user-provided string by using a scanner, converting input to lowercase, and iterating characters with a vowel check.

Implement Java string compression using a StringBuilder to count consecutive characters and encode them as char followed by count, returning the compressed string only if shorter, reducing memory usage.

Find duplicates in a string using a case-insensitive Java method. Normalize to lowercase, split with regex, count with a hash map, and print duplicates with their counts.

Discover how to find missing numbers in a Java array using sorting, range checks, and a contains helper, then print results with an ArrayList of missing values.

Sort an unsorted integer array in ascending order, then remove duplicates by converting to a set and converting back to an array, demonstrating Java arrays, sets, and conversion.

Learn to find duplicate numbers in a Java array using a HashSet, looping through elements to identify and print duplicates such as 3 and 7.

Use a for loop in Java to traverse the numbers array and accumulate each element to compute the total. Print the final sum, 150.

Learn to sort an array in ascending order with bubble sort in Java, using a main method, array initialization, element swapping, and printing the sorted result.

learn how to compare two hash sets for equality using the equals method, demonstrating that order doesn't matter when the sets contain the same elements.

Identify the first non-repeating element in an integer array by using a linked hash map to track frequencies in insertion order, then output a message if none exists.

Learn to implement a Java program that uses an array list to find the index of a target element, returning the first occurrence or -1 if not found.

Learn to create a hash map of country capitals, populate it with put, print the map, and find the country for a given capital by iterating its entry set.

Print the elements of an int array in reverse order by starting at the last index (length minus one) and printing each value.

Move all zeros to the end of an array in Java using a two-pointer approach, preserving the order of non-zero elements. Use a swap-based method and see a concrete example.

Learn to remove elements greater than a given value from a Java ArrayList using an iterator to modify the list in place, with a threshold example of ten.

Learn a Java program to find missing numbers in an array by sorting, identifying the range, and collecting absent values in an ArrayList for output.

implement a Java program that finds the intersection of two arrays using nested loops to compare elements, printing common values found in both arrays.

Learn to find the second smallest and second largest numbers in an array without sorting, by tracking min, max, second min, and second max, while handling duplicates.

Learn how to compare two arrays in Java using Arrays.equals, ensuring identical size, items, and order, with a simple main method and clear output messages.

Master merging two ascending sorted arrays in Java by building a merged array, iterating with three indices, comparing elements, handling leftovers, and printing the merged, sorted array.

Use a two-pointer technique to move negative numbers to the start of an array, with negatives first and positives last. Swap in place to achieve this O(n) arrangement.

Discover how to search an element in a Java array with linear search, including input setup, filling the array, performing the scan, and reporting the index or not found.

Rotate a Java array to the right by k using a three-reverse algorithm, applying modulus to wrap around, and print the results from the main method.

In Java, learn to check two arrays for quality by verifying equal length and identical elements in order, using a boolean check and a main method to report results.

Learn how to find the common elements between two arrays in Java using nested loops, comparing each element and printing matches, then using break to move to the next element.

Implement a Java program to find the last occurrence of a target in a sorted array using binary search and two-pointer technique, returning its index or -1 if not found.

Master binary search in Java by understanding how to search a sorted array, calculate middle safely, and adjust left and right bounds until the target is found or not present.

Develop a Java program that generates all substrings of a given string by using nested loops and the substring method, printing every possible starting and ending index.

learn to find the length of the longest substring without repeating characters using a sliding window and a hash map in Java, with two pointers and last-index tracking.

Implement a Java program using the sliding window technique to find the first negative number in every k-sized window, returning zero when none and producing the results as a list.

Discover how to compute the length of the longest substring without repeating characters using a sliding window, two pointers, and a hash map in Java.

Write a Java program that creates a string linked list of city names, adds elements to the beginning and end, and prints the final list.

Learn to implement a stack in Java using two arrays, performing push, pop, peek, and isEmpty while tracking top indices and capacity.

Implement a Java program to find the middle element of a linked list by building the list, handling empty lists, computing the middle index as size/2, and returning the value.

Apply the two-pointer technique to find the intersection of two sorted arrays, using i and j to traverse arrays, add common elements to a list, and print the result.

Learn to move all zeros to the end of an array using a single pass with the two-pointer technique, preserving non-zero order through in-place swaps.

Learn to reverse an array in place using the two-pointer technique in Java for sdet interview coding challenges, swapping left and right elements to produce the reversed sequence.

Using a two-pointer approach on a sorted array, this lecture demonstrates a Java method hasPairWithSum that returns true when any pair sums to the target, with a main test.

Reverse a string without loops by using recursion: reverse the rest of the string and append the first character, with a base case for an empty string.

Use a sliding window with a hash map to find the length of the longest substring without repeating characters. Update the window by the last-seen indices to keep it unique.

Learn to remove duplicate characters from a string in Java using a 256 sized boolean array to track seen ASCII characters, and build the result with a string builder.

Design and implement a Java program to find the first non-repeating character in a string using a linked hash map to count occurrences and identify the first unique character.