括号匹配算法

求助帖

返回一个表达式中的方法的左右括号的对应的索引位置,最好使用正则实现

如:Math.abs(Number(333.777555).toFixed(3)) - Number(123321.44455).toFixed(3)

返回左右括号的对应的索引位置为[{8,38},{15,26},{35,37},{48,61},{70,72}]

import java.util.*;
import java.util.stream.Collectors;

public class Test {

    public static void main(String [] args){
        Stack<Integer> stack = new Stack<Integer>();
        Map keys=new HashMap<>();
        String str="Math.abs(Number(333.777555).toFixed(3)) - Number(123321.44455).toFixed(3)";
        for(int i=0;i<str.length();i++){
            char c=str.charAt(i);
            if(c=='('){
                stack.push(i);
            }
            if(c==')'){
                keys.put(stack.peek(),i);
                stack.pop();
            }
        }
        System.out.println(sortByKey(keys));
    }

    public static <K, V extends Comparable<? super V>> Map<K, V> sortByValue(Map<K, V> map) {
        Map<K, V> result = new LinkedHashMap<>();

        map.entrySet().stream()
                .sorted(Map.Entry.<K, V>comparingByValue()
                ).forEachOrdered(e -> result.put(e.getKey(), e.getValue()));
        return result;

    }
    public static <K extends Comparable<? super K>, V > Map<K, V> sortByKey(Map<K, V> map) {
        Map<K, V> result = new LinkedHashMap<>();

        map.entrySet().stream()
                .sorted(Map.Entry.<K, V>comparingByKey()
                        ).forEachOrdered(e -> result.put(e.getKey(), e.getValue()));
        return result;
    }

}

 

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转载自blog.csdn.net/simplemurrina/article/details/109086437