按照年-月-日输入日期计算该日期是该年第几天

package com.zhidi.loop;

import java.util.Scanner;

public class Mouyitian {
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        System.out.println("请输入年份：");
        int year=sc.nextInt();
        System.out.println("请输入月份:");
        int month=sc.nextInt();
        System.out.println("请输入该月几号:");
        int data=sc.nextInt();
        int sum=0;
        int m;
        for(m=1;m<month;m++){
        switch(month){
        case 1:
        case 3:
        case 5:
        case 7:
        case 8:
        case 10:
        case 12:
            sum+=31;
            break;
        case 4:
        case 6:
        case 9:
        case 11:
            sum+=30;
            break;
        case 2:
            if(year%4==0 && (year%100!=0)||(year%400==0)){
                sum+=29;
            }else{
                sum+=28;
            }

        }
    }
        System.out.println("该日期是本年的第"+(sum+data)+"天");
    }
}