#include<stdio.h>



void NextTime(int day, int month, int year)
{
    // count day and month
    day = day + 1;
    printf("Next time: ");
    if(month == 1 || month == 3 || month == 5 || month == 7 || month == 9 || month == 11)
    {

        if(day > 31 && month < 12)
        {
           printf("1/%d/", month + 1);
        }
        else if(day <= 31 && month < 12)
        {
            printf("%d/%d/",day ,month);
        }
    }

    else if(month == 4 || month == 6 || month == 8 || month == 10 || month == 12)
    {
        if(day > 30 && month == 12)
        {
            printf("1/1/");
        }
        else if(day > 30 && month < 12)
        {
            printf("1/%d/", month + 1);
        }
        else if(day <= 30 && month <= 12)
        {
            printf("%d/%d/", day, month);
        }
    }
    else if(month == 2)
    {
        if(day > 28)
        {
        printf("1/3/");
        }
        else if(day <= 28)
        {
            printf("%d/2/", day);
        }
    }


//count year
  if( day > 30 && month == 12)
  {

     printf("%d", year + 1);
  }
  else if(day <= 31 && month < 12 || day > 31 && month < 12 )
  {
    printf("%d", year);
  }
}



void main()
{
  int day, month, year;


  //check input data
do
{
  do
  {
      printf("enter day: ");
      scanf("%d", &day);
      if(day > 31 || day <= 0)
      {
          printf(">>ERROR! day <= 30\n");
      }
  }while(day > 31 || day <= 0);

  do
  {
     printf("enter month: ");
     scanf("%d", &month);
     if(month > 12 || month < 1)
     {
         printf(">>ERROR! month >= 12\n");
     }
  }while(month > 12 || month < 1);

  if(month == 2 && day > 28 || month == 4 && day > 30 ||
       month == 6 && day > 30 || month == 8 && day > 30 ||
       month == 10 && day > 30 || month == 12 && day > 30)
  {
      printf(">>ERROR! day of month\n");
      printf("month [2] : 28 day\n");
      printf("month [4] [6] [8] [10] [12] : 30 day\n");
      printf("month [1] [3] [5] [7] [9] [11] : 31 day\n\n");
  }

}while(month == 2 && day > 28 || month == 4 && day > 30 ||
       month == 6 && day > 30 || month == 8 && day > 30 ||
       month == 10 && day > 30 || month == 12 && day > 30);

  do
  {
     printf("enter year: ");
     scanf("%d", &year);
     if(year < 2000)
     {
         printf(">>ERROR! year >= 2000");
     }
  }while(year < 2000);


  NextTime(day, month, year);
}