JAVA入门------输入年月日，计算日期是今年的第几天

import java.util.Scanner;
public class Demo {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
System.out.print("请输入今天的年份：");
int year = scan.nextInt();
System.out.print("请输入今天的月份：");
int month = scan.nextInt();
System.out.print("请输入今天的日期：");
int day = scan.nextInt();
int count = 0;
int days = 0;
if (year > 0 && month > 0 && month < 13 && day > 0 && day < 32) {
for (int i = 1; i < month; i++) {
switch (i) {
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
days = 31;
break;
case 4:
case 6:
case 9:
case 11:
days = 30;
break;
case 2: {
if ((year % 4 == 0 && year % 1 != 0) || (year % 400 == 0)) {
days = 29;
} else {
days = 28;
}
break;
}
}
count = count + days;
}
count = count + day;
System.out.println("今天是" + year + "年的第" + count + "天");
} else
System.out.println("数据输入错误！");
}
}