输入年、月、日，计算其为星期几

/*
Enter year:(e.g., 2012): 2015
Enter month: 1-12: 1
Enter the day of the month: 1-31: 25
Day of the week is Sunday.

Enter year:(e.g., 2012): 2012
Enter month: 1-12: 5
Enter the day of the month: 1-31: 12
Day of the week is Saturday.

*/
import java.util.Scanner;

public class DayOfTheWeek {
public static void main (String[] args) {
Scanner input = new Scanner(System.in);
int h, q, m, j, k;
/******************************************************
* h: is the day of the week.
* q: is the day of month.
* m: is the month.
* j: is the century.
* k: is the year of the century.
******************************************************/
System.out.print("Enter year:(e.g., 2012): ");
j = input.nextInt();
System.out.print("Enter month: 1-12: ");
m = input.nextInt();
if (m == 1 || m == 2) {
if (m == 1)
m = 13;
else
m = 14;
k = (j - 1) % 100;
j /= 100;
}
else {
k = j % 100;
j /= 100;
}
System.out.print("Enter the day of the month: 1-31: ");
q = input.nextInt();
h = (q + 26 * (m + 1) / 10 + k + k / 4 + j / 4 + 5 * j) % 7;

System.out.print("Day of the week is ");
switch (h) {
case 0: System.out.println("Saturday.");  break;
case 1: System.out.println("Sunday.");  break;
case 2: System.out.println("Monday.");  break;
case 3: System.out.println("Tuesday."); break;
case 4: System.out.println("Wednesday.");   break;
case 5: System.out.println("Thursday.");    break;
case 6: System.out.println("Friday.");  break;
}
}
}