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);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNextLine()) { // 注意 while 处理多个 case
            String s = in.nextLine();
            char[] chars = s.toCharArray();

            int en = 0, space = 0, num = 0, other = 0;
            for (char c : chars) {
                if (c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z') {
                    en ++;
                    continue;
                }
                if (c == ' ') {
                    space ++;
                    continue;
                }
                if (c >= '0' && c <= '9') {
                    num ++;
                    continue;
                }
                other ++;
            }
            System.out.println(en);
            System.out.println(space);
            System.out.println(num);
            System.out.println(other);
        }
    }
}