通配符匹配

题目描述

问题描述：在计算机中，通配符一种特殊语法，广泛应用于文件搜索、数据库、正则表达式等领域。现要求各位实现字符串通配符的算法。
要求：
实现如下2个通配符：
*：匹配0个或以上的字符（字符由英文字母和数字0-9组成，不区分大小写。下同）
？：匹配1个字符

输入：
通配符表达式；
一组字符串。

输出：
返回匹配的结果，正确输出true，错误输出false

输入描述:

先输入一个带有通配符的字符串，再输入一个需要匹配的字符串

输出描述:

返回匹配的结果，正确输出true，错误输出false

示例1

输入

te?t*.*
txt12.xls

输出

false

 

AC代码（dp）：

import java.util.Objects;
import java.util.Scanner;

/**
 * 1. if '*', dp[i][j] = dp[i][j-1] || dp[i-1][j]
 * 2. else dp[i][j] = dp[i-1][j-1] && （a[i]==b[j] || a[i] == '?')
 */
public class Main {

    public static Boolean matching(String regularStr, String matchingStr) {
        int regularLen = regularStr.length();
        int matchingLen = matchingStr.length();
        Boolean dp[][] = new Boolean[regularLen + 1][matchingLen + 1];
        dp[0][0] = true;
        for (int i = 0; i < regularLen; i++) {
            dp[i + 1][0] = false;
        }
        for (int i = 0; i < matchingLen; i++) {
            dp[0][i + 1] = false;
        }
        for (int i = 0; i < regularLen; i++) {
            for (int j = 0; j < matchingLen; j++) {
                if (Objects.equals(regularStr.charAt(i), '*')) {
                    dp[i + 1][j + 1] = dp[i + 1][j] || dp[i][j + 1];
                } else {
                    dp[i + 1][j + 1] = dp[i][j] &&
                            (Objects.equals(regularStr.charAt(i), matchingStr.charAt(j)) ||
                                    (Objects.equals(regularStr.charAt(i), '?')));
                }
            }
        }
        return dp[regularLen][matchingLen];
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNextLine()) {
            String regularStr = scanner.nextLine();
            String matchingStr = scanner.nextLine();
            System.out.println(matching(regularStr, matchingStr));
        }
    }
}

 

dfs:

import java.util.Objects;
import java.util.Scanner;

public class Main {

    public static Boolean matching(String regularStr, String matchingStr, int i, int j) {
        if (i >= regularStr.length() && j >= matchingStr.length()) {
            return true;
        }
        if (i >= regularStr.length() || j >= matchingStr.length()) {
            return false;
        }
        if (Objects.equals(regularStr.charAt(i), '*')) {
            return matching(regularStr, matchingStr, i + 1, j) ||
                    matching(regularStr, matchingStr, i, j + 1) ||
                    matching(regularStr, matchingStr, i + 1, j + 1);
        } else if (Objects.equals(regularStr.charAt(i), '?')) {
            return matching(regularStr, matchingStr, i + 1, j + 1);
        } else if (Objects.equals(regularStr.charAt(i), matchingStr.charAt(j))) {
            return matching(regularStr, matchingStr, i + 1, j + 1);
        }
        return false;
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNextLine()) {
            String regularStr = scanner.nextLine();
            String matchingStr = scanner.nextLine();
            System.out.println(matching(regularStr, matchingStr, 0, 0));
        }
    }
}

 

java match:

import java.util.Scanner;
public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while(sc.hasNext()){
            String zhengze = sc.next();
            String s = sc.next();
            zhengze = zhengze.replaceAll("\\?","[\\\\w]{1}");
            zhengze = zhengze.replaceAll("\\*","[\\\\w]*");
            System.out.println(s.matches(zhengze));
        }
        sc.close();
    }
}