The number of days of training algorithm questions computing Java Blue Bridge Cup

Questions algorithm to calculate the number of days of training

Requirements:　
writing a function evaluation on a certain day (**** ** **) is the first few days of the year. Tip: To consider leap year, leap year, February is 29 days (leap year conditions: a multiple of 4 but not multiple of 100, or multiples of 400). Write the main function, enter the date, test the function and output.
Input format:
　　Press "yyyy mm dd" date input format
output formats:
　　outputs the calculation result by an integer
sample input:
1,990,510
Sample Output:
130
data size and conventions:
　　date valid according to the actual input

Code:

import java.util.Scanner;

public class 天数计算
{
	// 定义函数计算天数
	public static int Day(int year, int month, int day) {
		int sum = 0;
		for (int i = 1; i < month; i++)
		{
			switch (i)
			{
			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:
				//判断是否为闰年
				if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
				{
					sum += 29;
				} else
				{
					sum += 28;
				}
			default:
				break;
			}

		}
		//返回当前年的值
		return sum + day;
	}

	public static void main(String[] args) {
		// 　编写函数求某年某月某日（**** ** **）是这一年的第几天 。提示：要考虑闰年，
		// 闰年的2月是29天（闰年的条件：是4的倍数但不是100的倍数，或者是400的倍数）。
		// 编写主函数，输入年月日，测试该函数并输出结果。
		Scanner sc = new Scanner(System.in);
		//输入年月日
		int year = sc.nextInt();
		int month = sc.nextInt();
		int day = sc.nextInt();
		System.out.println(Day(year, month, day));//调用函数并且输出
	}

}

Sample input:

1990 5 10

Sample output:

130