Reddit Clock CS Question in C

#include <stdio.h>

typedef struct{
  int h,m,s;
}Clock;
void startClock(Clock *clock){
  clock->h = 0;
  clock->m = 0;
  clock->s = 0;
}
void incClock(Clock *clock){
  clock->s ++;
  if (clock->s>=60){
    clock->s = 0;
    clock->m ++;
    if (clock->m>=60){
      clock->m = 0;
      clock->h ++;
      if (clock->h>12){
    clock->h = 1;
      }
    }
  }
}
void decClock(Clock *clock){
  clock->s --;
  if (clock->s<0){
    clock->s = 59;
    clock->m --;
    if (clock->m<0){
      clock->m = 59;
      clock->h --;
      if (clock->h<=0){
    clock->h = 12;
      }
    }
  }
}
int getSecs(Clock *clock){
  return clock->s + clock->m*60 + clock->h*3600;
}
int main(){
  Clock clock1;
  Clock clock2;
  startClock(&clock1);
  startClock(&clock2);
  int i,count=0;
  for (i=0;i<60*60*24;i++){
    if (getSecs(&clock1) == getSecs(&clock2)){
      count++;
    }
    incClock(&clock1);
    decClock(&clock2);
  }
  printf("Count : %d\n",count);
  return 0;
}