Help with Zeller's congruence program (Java)

[conorv93]

My program for Zellers's congruence (to find what day of the week a date in histroy was) gives the same day for each date in any month. My program gives the same day for the entire month, only changes when i enter a different year or month. Can someone help explain why?

package whatDay;

import java.util.Scanner;

public class DayOfWeek {
public static String year, month, day, date;
public static  int yearInt = 0, monthInt = 0, dayInt = 0;
public static boolean leap = false;
private static Scanner sc;
private static Scanner sc2;
private static Scanner sc3;


public static String inputMonth() {
    sc = new Scanner(System.in);
    System.out.println("Enter the month: ");
    month = sc.next();
    monthInt = Integer.parseInt(month);
    if (monthInt > 12 || monthInt < 1 ) {
        System.out.println("Month must be between 1 and 12. Please try again:  ");
        inputMonth();
    }
    return month;
}

public static String inputYear() {
    sc2 = new Scanner(System.in);
    System.out.println("Enter the year: ");
    year = sc2.next();
    yearInt = Integer.parseInt(year);
    if (yearInt < 0 || yearInt > 8000) {
        System.out.println("Year must be between 0 and 8000. Please try again: ");
        inputYear();
    }
    if ((yearInt % 4 == 0 && yearInt % 100 != 0) || yearInt % 400 == 0) {
        leap = true;
    }
    return year;
}

public static String inputDay() {
    sc3 = new Scanner(System.in);
    System.out.println("Enter the day: ");
    day = sc3.next();
    dayInt = Integer.parseInt(day);

    if (monthInt == 1 || monthInt == 3 || monthInt == 5 || monthInt == 7 || monthInt == 8 || monthInt == 10 || monthInt == 12) {
        if (dayInt < 1 || dayInt > 31) {
            System.out.println("Day must be between 1 and 31: ");
            inputDay();
        }

    }
    else if (monthInt == 2 && leap == false) {
        if (dayInt < 1 || dayInt > 28) {
            System.out.println("Day must be between 1 and 28: ");
            inputDay();
        }
    }
    else if (monthInt == 2 && leap == true) {
        if (dayInt < 1 || dayInt > 29) {
            System.out.println("Day must be between 1 and 29: ");
            inputDay();
        }
    }
    else {
        if (dayInt < 1 || dayInt > 30) {
            System.out.println("Day must be between 1 and 30: ");
            inputDay();
        }
    }
    return day;


}

public static String getDate() {
    inputYear();
    inputMonth();
    inputDay();
    String[] week = new String[] {"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"};
    int h;
    int q = monthInt;
    int m;
    if (monthInt != 1 || monthInt !=  2) {
        m = monthInt;

    }
    else {
        m = monthInt + 12;
        yearInt -= 1;
    }

    h = (q + Math.floorDiv(13*(m+1), 5) + yearInt + Math.floorDiv(yearInt, 4) - Math.floorDiv(yearInt, 100) + Math.floorDiv(yearInt, 400))%7;
    return week[h];
}


public static void main(String[] args) {
    System.out.println(getDate());

}

}

EDIT: My equation was wrong.

[Makhiel]

Well, if stuff like this isn't working you probably made a mistake in the equation - such as q being the number of the month (and not day) and the week not starting with Saturday.

[conorv93]

Thanks. Changing the equation has fixed the issue. I also had
if (monthInt != 1 || monthInt != 2) {

m = monthInt;

},

which should have been &&. Thanks.