题解 | #【模板】栈#
【模板】栈
https://www.nowcoder.com/practice/104ce248c2f04cfb986b92d0548cccbf
import java.util.*;
class Stack1{
int maxSize ;
int size = 0 ;
int top = 0 ;
int[] data ;
public Stack1(int maxSize){
this.maxSize = maxSize ;
this.data = new int[maxSize] ;
}
public void push(int x){
if(this.size == this.maxSize){
System.out.println("error") ;
}else{
data[this.top++] = x ;
this.size++;
}
}
public void pop(){ //出栈
if(this.size == 0){
System.out.println("error");
}else{
System.out.println(data[--this.top]);
this.size-- ;
}
}
public void top(){ //输出栈顶元素
if(this.size == 0){
System.out.println("error");
}else {
System.out.println(data[top - 1 ]);
}
}
}
public class Main{
public static void main(String[] args){
Scanner s = new Scanner(System.in) ;
int n = Integer.parseInt(s.nextLine());
Stack1 q = new Stack1(n);
while(s.hasNextLine()){
String str = s.nextLine();
String[] arr = str.split(" ");
if(arr[0].equals("push")){
q.push(Integer.parseInt(arr[1])) ;
}else if(arr[0].equals("pop")){
q.pop() ;
}else{
q.top() ;
}
}
}
}
