stack

栈（stack）是一种遵循先入后出逻辑的线性数据结

java

    /**
    * 比stack和linkedlist更快 <br>
    * 线程不安全
    */
    public class ArrayDequeDemo {
        public static void main(String[] args) {
            Deque<Integer> stack = new ArrayDeque<>();
            stack.push(1);
            stack.push(2);
            Integer peek = stack.peek();
            System.out.println("peek = " + peek);
            while (!stack.isEmpty()) {
                Integer o = stack.pop();
                System.out.println(o);
            }
        }
    }

    public class StackDemo {
        public static void main(String[] args) {
            Stack<Integer> stack = new Stack<>();
            stack.push(1);
            stack.push(2);
            stack.push(3);
            if (!stack.isEmpty()) {
                Integer peek = stack.peek(); // watch and keep
                System.out.println(peek);
                int search = stack.search(peek); // return distance from stack peek : 1-based indexing
                System.out.println(search);
            }
            while (!stack.isEmpty()) {
                Integer pop = stack.pop();
                System.out.println(pop);
            }
        }
    }

    public class LinkedListDemo {
        public static void main(String[] args) {
            Deque<Integer> stack = new LinkedList<>();
            stack.push(1);
            stack.push(2);
            stack.push(3);
            Integer peek = stack.peek();
            System.out.println("peek = " + peek);
            while (!stack.isEmpty()) {
                Integer o = stack.pop();
                System.out.println(o); // 3 2 1
            }
        }
    }

cpp