题解 | #统计字符#

import java.util.Scanner;

// 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);
        String str = in.nextLine();

        int yw = 0;
        int kg = 0;
        int sz = 0;
        int qt = 0;

        for (int i = 0; i < str.length(); i++) {
            char c = str.charAt(i);
            if ((c >= 'a' && str.charAt(i) <= 'z') || (str.charAt(i) >= 'A' && str.charAt(i) <= 'Z')) {
                yw++;
            } else if (str.charAt(i) == ' ') {
                kg++;
            } else if (str.charAt(i) >= '0' && str.charAt(i) <= '9') {
                sz++;
            } else {
                qt++;
            }
        }
        System.out.print(yw + "\n" + kg + "\n" + sz + "\n" + qt);
    }
}