65 lines
1.6 KiB
Java
65 lines
1.6 KiB
Java
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package Stack;
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/**
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* 顺序栈(基于数组实现)
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* Author: PeiJiaNi
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*/
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public class StackBaseArray {
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private int[] items; // 数组
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private int count; // 栈中元素个数
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private int length; // 栈空间大小
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public StackBaseArray(int capactiy) {
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this.items = new int[capactiy];
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this.count = 0;
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this.length = capactiy;
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}
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/**
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* 入栈操作 时间复杂度O(1)
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* @param item 要入栈的元素
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* @return 入栈成功则返回true,否则返回false
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*/
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public boolean push(int item) {
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if(count == length) {
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System.out.println("当前栈已满，无法进行入栈操作");
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return false;
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}
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items[count] = item;
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++count;
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return true;
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}
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/**
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* 出栈操作 时间复杂度O(1)
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* @return 如果栈内不为空，则返回栈顶元素，否则返回-1
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*/
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public int pop(){
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if(count == 0) {
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System.out.println("当前栈已空，无法进行出栈操作");
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return -1;
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}
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// 返回下标为 count-1 的数组元素，并且栈中元素个数count-1
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return items[--count];
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}
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public static void main(String[] args){
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StackBaseArray stack = new StackBaseArray(6);
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stack.push(1);
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stack.push(2);
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stack.push(3);
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stack.push(4);
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stack.push(5);
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System.out.println(stack.pop());
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System.out.println(stack.pop());
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System.out.println(stack.pop());
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System.out.println(stack.pop());
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System.out.println(stack.pop());
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}
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}
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