题解 | 字符串匹配

import java.util.*;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        Set<String> set = new HashSet<>();
        // 注意 hasNext 和 hasNextLine 的区别
        String s1 = in.next();
        in.nextLine();
        String s2 = in.next();
        int count = 0;
        for (int i=0; i<s1.length(); i++){
            if (s1.length() - i < s2.length())break;
            int j;
            for (j=i; j<s1.length() && j-i < s2.length(); j++){
                if (s1.charAt(j) == s2.charAt(j-i) || s2.charAt(j-i) == '?')continue;
                else break;
            }
            if (j-i == s2.length())set.add(s1.substring(i,j));
        }
        System.out.print(set.size());
    }
}