Program to check which week day is the first day of an year

import javax.swing.JOptionPane;
public class years {

public static void main(String[] args) {
int y, ref=2014,i,leap=0, ma, ac,day,k, d=3,a;
System.out.print(" 1=mon, 2= tue, 3= wed, 4=thrus, 5=fri, 6= sat, 7= sun");
y=Integer.parseInt(JOptionPane.showInputDialog("enter an year"));
if(y>ref)
{
day=y-ref;
k=day+d;
ma=k%7;
for(i=ref; i<y; i++)
{
if((i%4==0 && i%100!=0) || (i%400==0))
leap++;
}
if(leap==0)
{
if(ma==0)
System.out.print("   day is : "+ma+7);
else
System.out.print("   day is : "+ma);
}
else
{

ac=ma+leap;
a=ac%7;
if (a==0)
System.out.print("   day is : "+a+7);
else
System.out.print("   day is : "+a);
}
}
else if(y==ref)
System.out.print("  day is " +3 );
else if(y<ref && y>0)
{
day=ref-y;
k=d-day;
if(k<0)
k=k%7+7;
ma=k%7;
for(i=ref; i>=y; i--)
{
if((i%4==0 && i%100!=0) || (i%400==0))

leap++;
}
if(leap==0)
{
if(ma==0)
System.out.print("   day is : "+ma+7);
else
System.out.print("   day is : "+ma);
}
else
{

ac=ma-leap;
if(ac<0)
ac=ac%7+7;
a=ac%7;
if (a==0)
System.out.print("   day is : "+a+7);
else
System.out.print("   day is : "+a);
}
}
else
System.out.print("invalid year entered");
}

}

output:
1=mon, 2= tue, 3= wed, 4=thrus, 5=fri, 6= sat, 7= sun
enter year 2000
day is 6