import java.util.Scanner; public class Test2 { public static void main(String[] args) { //局部变量使用前一定要初始化 int lowCount = 0,upperCount=0,numCount=0,otherCount=0; Scanner sc=new Scanner(System.in); System.out.println("请输入字符串:"); String str=sc.next(); char[] chars=str.toCharArray(); for (int i = 0; i < chars.length; i++) { if(97<=chars[i]&&chars[i]<=122){ //小写字母 lowCount++; } else if(65<=chars[i]&&chars[i]<=90){ upperCount++; } else if(48<=chars[i]&&chars[i]<=57){ numCount++; } else{ otherCount++; } } System.out.println("大写字母个数:"+upperCount); System.out.println("小写字母个数:"+lowCount); System.out.println("数字个数:"+numCount); System.out.println("其他字符个数:"+otherCount); } }