题解 | #统计字符#

import java.util.*;

public class Main{
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        while (scan.hasNext()) {
            String input = scan.nextLine();
            String str1 = input.replaceAll("[^a-zA-Z]","");
            String str2 = input.replaceAll("[^ ]","");
            String str3 = input.replaceAll("[^0-9]","");
            String str4 = input.replaceAll("[a-zA-Z0-9 ]","");
            System.out.println(str1.length());
            System.out.println(str2.length());
            System.out.println(str3.length());
            System.out.println(str4.length());
        }
    }
}