week8 作业

import java.util.HashSet;
import java.util.Set;
public class ListMergeTest {
    static Node test(Node root1, Node root2) {
        if (root1 == null || root2 == null) return null;
        if (root1 == root2) return root1;
        Set<Node> nodes = new HashSet<>();
        int count = 0;
        while(root1 != null && root2 != null) {
            Node curr = root1;
            nodes.add(curr);
            root1 = root1.next;
            count ++;
            if (nodes.size() != count) return curr;
            curr = root2;
            nodes.add(curr);
            root2 = root2.next;
            count ++;
            if (nodes.size() != count) return curr;
        }
        return null;
    }
    public static void main(String[] args) {
        Node sameNode = new Node(99).next(new Node(100));
        Node root1 = new Node(1).next(new Node(2)).next(new Node(3)).next(sameNode);
        Node root2 = new Node(11).next(new Node(12)).next(new Node(3)).next(null);
        Node result = test(root1, root2);
        System.out.println("sameNode value:" + (result == null ? "null" : result.value));
    }
    private static class Node {
        int value;
        Node next;
        public Node(int value) {
            this.value = value;
        }
        public Node next(Node next) {
            this.next = next;
            return this;
        }
    }
}