Java implementation input A certain date of the year, to determine this day is the first days of the year?

3. Enter a certain date of the year, to determine the day is the first days of the year.
Import Java.util.Scanner;
public class year{
public static void Main (string[] args) {
Scanner scan = new Scanner (system.in);
int ye =0, Mon = 1, day = 1;
int i;
int to = 0;
int a[]={0,31,28,31,30,31,30,31,31,30,31,30,31};
for (;;) {
System.out.print ("Please enter Year:");
Ye = Scan.nextint ();
if (ye<0) {
SYSTEM.OUT.PRINTLN ("Year should be greater than 0, please re-enter.") ");
Continue
}else{
Break
}
}
for (;;) {
System.out.print ("Please enter the month:");
Mon = Scan.nextint ();
if (mon<0) {
SYSTEM.OUT.PRINTLN ("Month should be between 1-12, please re-enter.") ");
Continue
}else{
Break
}
}
for (;;) {
System.out.print ("Please enter the day:");
Day = Scan.nextint ();
if ((ye%400 = = 0 && ye%100 = 0) | | ye%4 = 0) {//Determine if it is a leap year
a[2]=29;

}
if (Day > A[mon]) {
SYSTEM.OUT.PRINTLN (the date should be a valid value, please re-enter it.) ");
Continue
}else{
if (Mon = = 1) {//
to = day;
}else{
for (i = 0;i <= mon-1; i++) {
to + + a[i];
}
to + = day;
}

System.out.println ("The day is the first of the year" +to+ "Day");
Break
}
}
}

}