输入某年某月某日，判断这一天是这一年的第几天？

案例：输入某年某月某日，判断这一天是这一年的第几天？

方法一：

System.out.println("输入某年某月某日");
Scanner sc = new Scanner(System.in);
System.out.println("年：");
int year = sc.nextInt();
System.out.println("月：");
int mon = sc.nextInt();
System.out.println("日：");
int day = sc.nextInt();

//非闰年的每月天数
int arr1[] = {31,28,31,30,31,30,31,31,30,31,30,31};
//闰年的每月天数
int arr2[] = {31,29,31,30,31,30,31,31,30,31,30,31};

int yue = 0;
int tian = 0;
if(year%100!=0 && year%4 == 0){ 
//是闰年
if(mon < 2){
System.out.println(year+"年"+mon+"月"+day+"日是"+year+"的第"+day+"天。");
}else{
for(int i = 2;i <= mon;i++){
yue += arr2[i-2];
}
tian = yue + day;
System.out.println(year+"年"+mon+"月"+day+"日是"+year+"的第"+tian+"天。");
}
}else{
//不是闰年
if(mon < 2){
System.out.println(year+"年"+mon+"月"+day+"日是"+year+"的第"+tian+"天。");
}else{
for(int i = 2;i <= mon;i++){
yue += arr1[i-2];
}
tian = yue + day;
System.out.println(year+"年"+mon+"月"+day+"日是"+year+"的第"+tian+"天。");
}
}

方法二：
System.out.println("输入某年某月某日");
Scanner sc = new Scanner(System.in);
System.out.println("年：");
int year = sc.nextInt();
System.out.println("月：");
int mon = sc.nextInt();
System.out.println("日：");
int day = sc.nextInt();
//判断是否是闰年
GregorianCalendar gc = new GregorianCalendar();
boolean isLeapYear = gc.isLeapYear(year);
//二月份的天数
int ap = isLeapYear?29:28;
int d = 0;
switch(mon){
case 1:
d = day;
break;
case 2:
d = 31 + day;
break;
case 3:
d = 31 + ap + day;
break;
case 4:
d = 31 + ap + 31 + day;
break;
case 5:
d = 31 + ap + 31 + 30 + day;
break;
case 6:
d = 31 + ap + 31 + 30 + 31+ day;
break;
case 7:
d = 31 + ap + 31 + 30 + 31+ 30 + day;
break;
case 8:
d = 31 + ap + 31 + 30 + 31+ 30 + 31 + day;
break;
case 9:
d = 31 + ap + 31 + 30 + 31+ 30 + 31 + 31 + day;
break;
case 10:
d = 31 + ap + 31 + 30 + 31+ 30 + 31 + 31 + 30 + day;
break;
case 11:
d = 31 + ap + 31 + 30 + 31+ 30 + 31 + 31 + 30 + 31 + day;
break;
case 12:
d = 31 + ap + 31 + 30 + 31+ 30 + 31 + 31 + 30 + 31 + 30 + day;
break;
}
System.out.println("第"+d+"天。");