About the list: delete the specified element is inserted after the specified location or remove elements

Description: The idea is written in pseudo-code, in order to express meaning.

First, delete the list of nodes equal to val

Cur requires two nodes and PREV (as a precursor of the node cur)
to traverse the entire list, and compares a given val,
if they are equal: prev.next = cur.next;
if not equal: cur = cur.next;

Second, after the designated POS insertion, deletion node
is inserted: pos.next = Node;
node.next = pos.next;
Delete: pos.next = pos.next.next

code show as below:

```class Node {
int val;
Node next = null;

Node(int val) {
    this.val = val;
}

public String toString() {
    return String.format("Node(%d)", val);
}

}

{Solution class
public removeElements the Node (the Node head, int Val) {
the Node result = null;
the Node Last = null; // record the last current result node

    Node cur = head;
    while (cur != null) {
        if (cur.val == val) {
            cur = cur.next;
            continue;
        }

        Node next = cur.next;

        cur.next = null;
        if (result == null) {
            result = cur;
        } else {
            last.next = cur;
        }

        last = cur;

        cur = next;
    }

    return result;
}

}

public class MyLinkedList {
public static void main(String[] args) {
Node head = new Node(1);
head.next = new Node(2);
head.next.next = new Node(3);//pos
head.next.next.next = new Node(4);

    Node pos = head.next.next;
    pushAfter(pos, 100);//在pos之后入100

    // 1, 2, 3, 100, 4
}

private static void pushAfter(Node pos, int val) {
    Node node = new Node(val);

    node.next = pos.next;
    pos.next = node;
}

private static void popAfter(Node pos) {
    pos.next = pos.next.next;
}

}