Java 示例 - 使用堆栈反转字符串

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  问题描述

  如何使用堆栈反转字符串？
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  解决方案

  以下示例显示了如何在用户定义的方法 StringReverserThroughStack() 的帮助下使用堆栈反转字符串。

  
  import java.io.IOException;
  public class StringReverserThroughStack {
     private String input; 
     private String output;
     public StringReverserThroughStack(String in) {
        input = in;
     }
     public String doRev() {
        int stackSize = input.length(); 
        Stack theStack = new Stack(stackSize); 
        
        for (int i = 0; i < input.length(); i++) {
           char ch = input.charAt(i); 
           theStack.push(ch); 
        }
        output = "";
        while (!theStack.isEmpty()) {
           char ch = theStack.pop(); 
           output = output + ch; 
        }
        return output;
     }
     public static void main(String[] args) throws IOException {
        String input = "Java Source and Support";
        String output;
        StringReverserThroughStack theReverser = 
        new StringReverserThroughStack(input);
        output = theReverser.doRev();
        System.out.println("Reversed: " + output);
     }
     class Stack {
        private int maxSize;
        private char[] stackArray;
        private int top;
        
        public Stack(int max) {
           maxSize = max;
           stackArray = new char[maxSize];
           top = -1;
        }
        public void push(char j) {
           stackArray[++top] = j;
        }
        public char pop() {
           return stackArray[top--];
        }
        public char peek() {
           return stackArray[top];
        }
        public boolean isEmpty() {
           return (top == -1);
        }
     }
  }
  

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  结果

  上面的代码示例将产生以下结果。

  
  JavaStringReversal
  Reversed:lasreveRgnirtSavaJ
  

  以下是使用堆栈反转字符串的示例。

  
  import java.util.Scanner;
  class Stack {
     private int maxSize;
     private char[] stackArray;
     private int top;
     
     public Stack(int s) {
        maxSize = s;
        stackArray = new char[maxSize];
        top = -1; 
     } 
     public void push(char j) {
        stackArray[++top] = j;
     } 
     public char pop() {
        return stackArray[top--];
     } 
     public char peek() {
        return stackArray[top];
     } 
     public boolean isEmpty() { 
        return (top == -1);
     } 
     public boolean isFull() {
        return (top == maxSize - 1);
     }
  }
  public class Demo {
     public static void main(String[] args) {
        System.out.println("Enter a sentence: ");
        Scanner scan = new Scanner(System.in);
        String input = scan.nextLine();
        int stackSize = input.length();
        Stack theStack = new Stack(stackSize);
        
        for (int j = 0; j < input.length(); j++) {
           char ch = input.charAt(j);
           theStack.push(ch);
        } 
        while (!theStack.isEmpty()) {
           char ch = theStack.pop();
           System.out.println(ch);
        } 
     }
  }
  

  上面的代码示例将产生以下结果。

  
  Enter a sentence: 
  sai
  i
  a
  s