Simple Time Converter [C/C++]

#include<stdio.h>
#include<conio.h>
int a,b,c,d;
main()
{
      printf("****************************************\n");
      printf("*           Time Conversion            *\n");
      printf("*                                      *\n");
      printf("*     1] 60 secs = 1 min               *\n");
      printf("*     2] 60 min  = 1 hour              *\n");
      printf("*                                      *\n");
      printf("****************************************\n");
      printf("Input 1 for sec to min ; 2 for min to hour:   ");
      /*dL1nkx*/
      scanf("%d",&a);
      if ( a == 1)
      {/*dL1nkx*/
           printf("\n\nPlease Enter SECONDS: ");
           scanf("%d",&b);
           c = b/60;
           d = b%60;
           printf("\nIn %d secs there are %d min and %d secs ",b,c,d);
      }/*dL1nkx*/
      if ( a == 2)
      {
           printf("\n\nPlease Enter MINUTES: ");
           scanf("%d",&b);
           c = b/60;
           d = b%60;
           printf("\nIn %d mins there are %d hour and %d mins ",b,c,d);
      }
      if (a != 1 && a!=2)
      {
            printf("Please Enter 1 or 2 Only");/*dL1nkx*/
      }
      getch();
}