Calender program in C

//this is a calender program which accepts date in the format dd mm yyyy and prints day on this date
#include<stdio.h>
#include<conio.h>
int calmd(int n);
void main()
{
   
    int d,m,y,a,x,md;
    printf("Enter the date in format dd mm yyyy\n");
    scanf("%d %d %d", &d, &m, &y);
    if((m==2&&y%4==0&&d>29)||(m==2&&y%4!=0&&d>28))
        printf("Wrong date !\n Welcome to amancybertricks.blogspot.com");
    else if(((m==4||m==6||m==9||m==11)&&(d>30))||((m==1||m==3||m==5||m==7||m==8||m==10||m==12)&&(d>31)))
        printf("Wrong date !\n Welcome to amancybertricks.blogspot.com");

    else
    {
        printf("Welcome to amancybertricks.blogspot.com\n It is ");
    md = calmd(m);
    a = y*365+(y-1)/4+md+d;
    x = a%7;
    if((y%4==0)&&(m>2))
        x=x+1;
    switch(x)
    {
    case 1:
        printf("Saturday");
        break;
    case 2:
        printf("Sunday");   
        break;
    case 3:
        printf("Monday");
        break;
    case 4:
        printf("Tuesday");
        break;
    case 5:
        printf("wednessday");
        break;
    case 6:
        printf("Thrusday");
        break;
    default:
        printf("Friday");
        break;
    }
    }
    getch();
}
int calmd(int n)
//this program is Written by aman kumar singh
//for more about aman go to www.facebook.com/aman.kumarsingh
{ int md;
    if(n==1)
md=0;
else if(n==2)
md=31;
else if(n==3)
md=59;
else if(n==4)
md=90;
else if(n==5)
md=120;
else if(n==6)
md=151;
else if(n==7)
md=181;
else if(n==8)
md=212;
else if(n==9)
md=243;
else if(n==10)
md=273;
else if(n==11)
md=304;
else
md=334;
return md;
}