【Java数据结构】不带头单向循环链表

 

public class SingleLink<T> { private static class Entry<E>{ private Entry<E> next; private E value; public Entry(E value){ this.value = value; next = this; } } private Entry<T> headEntry; private Entry<T> tailEntry; public SingleLink(){ } public void addHead(T value){ Entry<T> newEntry = new Entry<>(value); if(headEntry == null){ headEntry = newEntry; tailEntry = newEntry; }else{ //1. newEntry.next = headEntry; //2 headEntry = newEntry; //3 tailEntry.next = headEntry; } } public void addTail(T value){ Entry<T> newEntry = new Entry<>(value); if(headEntry == null){ headEntry = newEntry; tailEntry = newEntry; }else { tailEntry.next = newEntry; newEntry.next = headEntry; tailEntry = newEntry; } } public void deleteHead(){ if(headEntry == null) return; //只有一个节点 //防止内存泄漏 headEntry.value = null; if(headEntry.next == headEntry){ headEntry = null; tailEntry = null; }else { tailEntry.next = headEntry.next; //更新新头 headEntry = headEntry.next; } } public void deleteTail(){} public void show(){ if(headEntry == null){ return; } Entry<T> p = headEntry; do{ System.out.print(p.value+" "); p=p.next; }while(p!=headEntry); } }