#include<conio.h>
#include<stdio.h>
main(void)
{
 int t;
 int y,d=1,i,m=1;
 printf("Enter the Year: ");
 scanf("%4u",&y);
 if(y<0)
 y=-y;
 printf("Enter the Month: ");
 scanf("%2u",&m);
 if(m<=0 || m>=12)
 m=1;
 i=y%4;
 printf("Enter the Day: ");
 scanf("%2u",&d);
 if (d>=1&&d<28)
 d=d+1;
 else if(d==i&&m==2)
 {d=1;
 m=3;}
 else if (d==30&&m==4||m==6||m==9||m==11)
 {d=1;
 m=m+1;}
 else if (d==31&&m==1||m==2||m==3||m==5||m==7||m==8||m==10)
{
 d=1;
 m=m+1;
 }
 else if(d==31&&m==12)
 { 
 d=1;
 m=1;
 y=y+1;
 }
 printf("Tomorrow's Date is\n  %d/%d/%d ",d,m,y);
 getch();
}

 

#include <time.h>
...
int main()
{
    int m = 11; // November
    int y = 2008;
    int d = 2;

   struct tm tm;
   // clear all members of the structure
   memset(&tm,0,sizeof(struct tm));

   tm.tm_year = y-1900;
   tm.tm_mon = m-1;
   tm.tm_day = d;
   // increment tomarrow
   tm.tm_mday++;
   mktime(&tm);

else if(d==i&&m==2)