IBM coding

import java.util.*;
public class PrintDuplicates {
    public static void printDuplicates(int[] arr) {
        Map<Integer, Integer> freq = new LinkedHashMap<>();
        for (int num : arr) {
            freq.put(num, freq.getOrDefault(num, 0) + 1);
        }
        for (Map.Entry<Integer, Integer> entry : freq.entrySet()) {
            if (entry.getValue() > 1) {
                for (int i = 0; i < entry.getValue() - 1; i++) {
                    System.out.print(entry.getKey() + " ");
                }
            }
        }
    }

    public static void main(String[] args) {
        printDuplicates(new int[]{10, 20, 20, 30, 30, 30, 40, 50, 50});
    }
}

from collections import Counter

def print_duplicates(arr):
    freq = Counter(arr)
    result = []
    for num, count in freq.items():
        if count > 1:
            result.extend([num] * (count - 1))
    print(*result)

print_duplicates([10, 20, 20, 30, 30, 30, 40, 50, 50])

public class DetectLoop {
    static class Node {
        int val;
        Node next;
        Node(int val) { this.val = val; }
    }

    public static boolean hasCycle(Node head) {
        if (head == null) return false;
        Node slow = head, fast = head;
        while (fast != null && fast.next != null) {
            slow = slow.next;
            fast = fast.next.next;
            if (slow == fast) return true;
        }
        return false;
    }
}

class Node:
    def __init__(self, val):
        self.val = val
        self.next = None

def has_cycle(head):
    slow, fast = head, head
    while fast and fast.next:
        slow = slow.next
        fast = fast.next.next
        if slow == fast:
            return True
    return False

import java.util.*;
public class PairWithSum {
    public static boolean hasPairWithSum(int[] arr, int target) {
        Set<Integer> seen = new HashSet<>();
        for (int num : arr) {
            if (seen.contains(target - num)) return true;
            seen.add(num);
        }
        return false;
    }

    public static void main(String[] args) {
        System.out.println(hasPairWithSum(new int[]{1, 4, 45, 6, 10, -8}, 16));
    }
}

def has_pair_with_sum(arr, target):
    seen = set()
    for num in arr:
        if target - num in seen:
            return True
        seen.add(num)
    return False

print(has_pair_with_sum([1, 4, 45, 6, 10, -8], 16))

public class DeleteNodesInRange {
    static class Node {
        int val;
        Node next;
        Node(int val) { this.val = val; }
    }

    public static Node deleteInRange(Node head, int low, int high) {
        Node dummy = new Node(0);
        dummy.next = head;
        Node prev = dummy, curr = head;

        while (curr != null) {
            if (curr.val >= low && curr.val <= high) {
                prev.next = curr.next;
            } else {
                prev = curr;
            }
            curr = curr.next;
        }
        return dummy.next;
    }
}

public class ReverseNumber {
    public static int reverse(int num) {
        int reversed = 0;
        while (num != 0) {
            int digit = num % 10;
            reversed = reversed * 10 + digit;
            num /= 10;
        }
        return reversed;
    }

    public static void main(String[] args) {
        System.out.println(reverse(12345));
    }
}

import java.util.Arrays;
public class ReverseArray {
    public static void reverse(int[] arr) {
        int start = 0, end = arr.length - 1;
        while (start < end) {
            int temp = arr[start];
            arr[start] = arr[end];
            arr[end] = temp;
            start++;
            end--;
        }
    }

    public static void main(String[] args) {
        int[] arr = {10, 20, 30, 40, 50};
        reverse(arr);
        System.out.println(Arrays.toString(arr));
    }
}

import java.util.Arrays;
public class BubbleSort {
    public static void bubbleSort(int[] arr) {
        int n = arr.length;
        for (int i = 0; i < n - 1; i++) {
            for (int j = 0; j < n - i - 1; j++) {
                if (arr[j] > arr[j + 1]) {
                    int temp = arr[j];
                    arr[j] = arr[j + 1];
                    arr[j + 1] = temp;
                }
            }
        }
    }

    public static void main(String[] args) {
        int[] arr = {64, 34, 25, 12, 22, 11, 90};
        bubbleSort(arr);
        System.out.println(Arrays.toString(arr));
    }
}

public class PrintLetterN {
    public static void printN(int size) {
        for (int i = 0; i < size; i++) {
            for (int j = 0; j < size; j++) {
                if (j == 0 || j == size - 1 || j == i) {
                    System.out.print("*");
                } else {
                    System.out.print(" ");
                }
            }
            System.out.println();
        }
    }

    public static void main(String[] args) {
        printN(5);
    }
}