题解 | #统计字符#

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String input = in.nextLine();
        //英文字符
        int ew = 0;
        //空格字符
        int kg = 0;
        //数字字符
        int sz = 0;
        //其他字符
        int qt = 0;
        for (int i = 0; i < input.length(); i++) {
            char c = input.charAt(i);
            if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
                ew++;
            } else if (c >= '0' && c <= '9') {
                sz++;
            } else if (c == ' ') {
                kg++;
            } else {
                qt++;
            }
        }
        System.out.println(ew);
        System.out.println(kg);
        System.out.println(sz);
        System.out.println(qt);
    }
}

解题思路:

1, 对每个字符进行遍历, 记录下相关字符的数量;

2, 按照顺序输出结果即可