目的：ES6标准下的JS数据结构的一些实现代码。（作为记录和启发）
内容：栈。（未完成，待继续）
一、数据结构
1、栈（先入后出）
// @ts-check
class Stack {
constructor() {
this.count = 0;
this.items = {};
}
push(element) {
this.items[this.count] = element;
this.count++;
}
pop() {
if (this.isEmpty()) {
return undefined;
}
this.count--;
const result = this.items[this.count];
delete this.items[this.count];
return result;
}
peek() {
if (this.isEmpty()) {
return undefined;
}
return this.items[this.count - 1];
}
isEmpty() {
return this.count === 0;
}
size() {
return this.count;
}
clear() {
/* while (!this.isEmpty()) {
this.pop();
} */
this.items = {};
this.count = 0;
}
toString() {
if (this.isEmpty()) {
return ‘‘;
}
let objString = `${this.items[0]}`;
for (let i = 1; i < this.count; i++) {
objString = `${objString},${this.items[i]}`;
}
return objString;
}
}
const stack = new Stack(); // new StackArray();
// using WeakMap to store Stack items we ensure true privacy
// console.log(Object.getOwnPropertyNames(stack));
// console.log(Object.keys(stack));
// console.log(stack.items);
console.log(‘stack.isEmpty() => ‘, stack.isEmpty()); // outputs true
stack.push(6);
stack.push(8);
console.log(‘stack after push 5 and 8 => ‘, stack.toString());
console.log(‘stack.peek() => ‘, stack.peek()); // outputs 8
stack.push(11);
console.log(‘stack.size() after push 11 => ‘, stack.size()); // outputs 3
console.log(‘stack.isEmpty() => ‘, stack.isEmpty()); // outputs false
stack.push(15);
stack.pop();
stack.pop();
console.log(‘stack.size() after push 15 and pop twice => ‘, stack.size());
2、队列
原文地址：https://www.cnblogs.com/xinkuiwu/p/11586955.html