java alex

gistfile1.java

import java.util.Random;

public class BirthdaySimulation
{

    public static void main(String [] args) {
        Random rand = new Random();
        int month = rand.nextInt(12);
        int day = getDayInMonth(month);
        
        int matches = 0;

        // Check how many matches we get out of 100 random dates
        for (int i = 0; i < 100; i++) {
            int month2 = rand.nextInt(12);
            int day2 = getDayInMonth(month);

            // If month and day are equal, we have a match
            if (month == month2 && day == day2) {
                matches++;
            }
        }

        System.out.println("We have " +  matches + "for month:" + month + " day:" + day);

    }

        // Get number of days in month, assuming the current year isn't a leap year
        public static int getDayInMonth(int month) {
            int monthDays[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

            if (month > 11 || month < 0) {
                return -1;
            } else {

                Random rand = new Random();
                return rand.nextInt(monthDays[month]);
            }
        }
}