java基础练习

package cn.leaveriver.practice;
import java.util.Scanner;

public class Demo01 {
    public static void main(String[] args) {
        int num = 0;
        int letterNum = 0;
        int spaceNum = 0;
        int other = 0;
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入一段字符：");
        String s = scanner.nextLine(); //读一行
        char[] chars = s.toCharArray();
        for (int i = 0; i < chars.length; i++) {
            char c = chars[i];
            if (c >= '0' && c <= '9'){ //0-9也可以用  48= 65 && c <= 90) || (c >= 97 && c < 122)){//A-Z 或者a-z
                letterNum++;
            }else if (c == 32){// 空格
                spaceNum++;
            }else {  //其他
                other++;
            }
        }
        System.out.println("其中数字有" + num + "个，字母有"+letterNum+"个，空格有"+spaceNum+"个，其他有"+other+"个。");
    }
}