java 使用栈匹配字符串符号

Posted 2020-11-17 花儿为何那样红

/**
 * 栈
 * Create by Administrator
 * 2018/6/11 0011
 * 上午 10:20
 **/
public class StackR {

    private int maxSixe;

    private char[] stackArray;

    private int top;

    public StackR(int s) {
        this.maxSixe = s;
        this.stackArray = new char[maxSixe];
        this.top = -1;
    }

    /**
     * 入栈
     * @param j
     */
    public boolean push(char j){
        if(isFull()){
            System.out.println("栈已满");
            return false;
        }else{
            this.stackArray[++top] = j;
            return true;
        }
    }

    /**
     * 出栈
     */
    public char pop(){
        return stackArray[top--];
    }

    /**
     * 查看
     * @return
     */
    public void peek(){
        System.out.println(stackArray[top]);
    }

    /**
     * 判断栈是否为空
     * @return
     */
    public boolean isEmpty(){
        return (top == -1);
    }

    /**
     * 判断栈是否满了
     * @return
     */
    public boolean isFull(){
        return (top == maxSixe-1);
    }
}

　　

public class BracketChecher {

    private String input;

    public BracketChecher(String input) {
        this.input = input;
    }

    public void check(){
        int stackSize = input.length();
        StackR stackR = new StackR(stackSize);
        for (int i = 0; i < stackSize; i++) {
            char ch = input.charAt(i);
            switch (ch){
                case ‘{‘:
                case ‘[‘:
                case ‘(‘:
                    stackR.push(ch);
                    break;
                case ‘}‘:
                case ‘]‘:
                case ‘)‘:
                    if(!stackR.isEmpty()){
                        char chx = stackR.pop();
                        if(ch == ‘}‘ && chx != ‘{‘ || ch == ‘]‘ && chx != ‘[‘ || ch == ‘)‘ && chx != ‘(‘){
                            System.out.println("Error:"+ch+" at "+i);
                        }
                    }else{
                        System.out.println("Error:"+ch+" at "+i);
                    }
                default:
                    break;
            }
        }
        if(!stackR.isEmpty()){
            System.out.println("Error: missing right delimiter");
        }
    }

    public static String getString() throws IOException{
        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        String s = br.readLine();
        return s;
    }

    public static void main(String[] args) throws IOException {
        while(true){
            System.out.flush();
            String input = getString();
            BracketChecher b = new BracketChecher(input);
            b.check();
        }
    }

　　测试控制台输入字符串：a{b(c]d}

　　结果：Error:] at 3