Create CodingInterview.java

CodingInterview.java

@@ -0,0 +1,99 @@
+import java.util.Scanner;
+
+public class CodingInterviewApp {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+
+        System.out.println("Welcome to the Coding Interview Practice App!");
+        System.out.println("Select a programming language: ");
+        System.out.println("1. Java");
+        System.out.println("2. Python");
+        System.out.println("3. JavaScript");
+
+        int selectedLanguage = scanner.nextInt();
+        scanner.nextLine(); // Consume the newline character
+
+        System.out.println("Choose a coding problem to solve:");
+        System.out.println("1. Palindrome Checker");
+        System.out.println("2. Fibonacci Sequence");
+        System.out.println("3. Factorial Calculator");
+
+        int selectedProblem = scanner.nextInt();
+        scanner.nextLine(); // Consume the newline character
+
+        String problemStatement = "";
+        switch (selectedProblem) {
+            case 1:
+                problemStatement = "Write a function to check if a given string is a palindrome.";
+                break;
+            case 2:
+                problemStatement = "Write a function to generate the first n numbers in the Fibonacci sequence.";
+                break;
+            case 3:
+                problemStatement = "Write a function to calculate the factorial of a non-negative integer.";
+                break;
+            default:
+                System.out.println("Invalid choice. Exiting the app.");
+                return;
+        }
+
+        System.out.println("Problem to solve: " + problemStatement);
+        System.out.println("Start coding! Type your solution below:");
+
+        String userSolution = scanner.nextLine();
+        System.out.println("Your solution: " + userSolution);
+
+        System.out.println("Run test cases (Y/N)?");
+        String runTests = scanner.nextLine();
+
+        if (runTests.equalsIgnoreCase("Y")) {
+            // Simplified test cases (assuming correct input from the user)
+            if (selectedProblem == 1) {
+                System.out.println("Test Case 1: " + isPalindrome(userSolution));
+                System.out.println("Test Case 2: " + isPalindrome("hello"));
+            } else if (selectedProblem == 2) {
+                System.out.println("Test Case 1: " + fibonacci(5));
+                System.out.println("Test Case 2: " + fibonacci(10));
+            } else if (selectedProblem == 3) {
+                System.out.println("Test Case 1: " + factorial(5));
+                System.out.println("Test Case 2: " + factorial(8));
+            }
+        }
+
+        System.out.println("Thank you for using the Coding Interview Practice App!");
+        scanner.close();
+    }
+
+    // Palindrome Checker
+    private static boolean isPalindrome(String str) {
+        String reversed = new StringBuilder(str).reverse().toString();
+        return str.equalsIgnoreCase(reversed);
+    }
+
+    // Fibonacci Sequence
+    private static int fibonacci(int n) {
+        if (n <= 1) {
+            return n;
+        }
+        int fib = 1;
+        int prevFib = 1;
+        for (int i = 2; i < n; i++) {
+            int temp = fib;
+            fib += prevFib;
+            prevFib = temp;
+        }
+        return fib;
+    }
+
+    // Factorial Calculator
+    private static int factorial(int n) {
+        if (n == 0) {
+            return 1;
+        }
+        int result = 1;
+        for (int i = 1; i <= n; i++) {
+            result *= i;
+        }
+        return result;
+    }
+}