write a program to set stop timer in C program

#include
#include
typedef struct
{
int h,m,s;
}TIME;
TIME calculater(TIME start, TIME stop,int check);
void main()
{
TIME start,stop,sum,diff;
int hh,mm,ss;
clrscr();
printf("Enter start time:\nHour:");
scanf("%d",&hh);
printf("\nMinutes:");
scanf("%d",&mm);
printf("\nSeconds:");
scanf("%d",&ss);
start.h=hh;
start.m=mm;
start.s=ss;
printf("Enter stop time:\nHour:");
scanf("%d",&hh) ;
printf("\nMinutes:");
scanf("%d",&mm);
printf("\nSeconds:");
scanf("%d",&ss);
stop.h=hh;
stop.m=mm;
stop.s=ss;
sum=calculater(start,stop,1);
printf("\nThe sum is\n");
printf("\n%dhh%dmm%dss",sum.h,sum.m,sum.s);
diff=calculater(start,stop,0);
printf("\nThe diff is\n");
printf("\n%dhh%dmm%dss",diff.h,diff.m,diff.s);
getch();
}
TIME calculater(TIME a, TIME b,int check)
{
TIME sum;
int x;
int temp;
if (check==1)
temp=a.h*3600+a.m*60+a.s+b.h*3600+b.m*60+b.s ;// meaning less to add
else
temp=((b.h*3600+b.m*60+b.s)-(a.h*3600+a.m*60+a.s)) ;

sum.s=temp%60;
temp/=60;
sum.m=temp%60;
sum.h=temp/60;
return sum;
}