在Java编程中,如何使用堆栈来反转字符串?
以下示例显示了如何使用堆栈在用户自定义的StringReverserThroughStack()
方法来反转字符串。
package com.yiibai;
import java.io.IOException;
public class StringReversalUsingStack {
private String input;
private String output;
public StringReversalUsingStack(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 String And Stack";
String output;
StringReversalUsingStack theReverser = new StringReversalUsingStack(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);
}
}
}
上述代码示例将产生以下结果 -
Reversed: kcatS dnA gnirtS avaJ
示例-2
以下是使用堆栈来反转字符串的另一个示例。
package com.yiibai;
import java.util.Scanner;
class Stack3 {
private int maxSize;
private char[] stackArray;
private int top;
public Stack3(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 StringReversalUsingStack2 {
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();
Stack3 theStack = new Stack3(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.print(ch);
}
}
}
上述代码示例将产生以下结果 -
Enter a sentence:
123abc
cba321