#include<stdio.h>
#include<stdlib.h>
#define err(s,x) {perror(s);exit(x);}
int main()
{
int hour=0,fen=0;
printf("Enter a 24-hour time:");
scanf("%d:%d",&hour,&fen);
if(hour>=24 || hour<0)
err("hour",1);
if(fen<0 || fen>=60)
err("fen",2);
if(hour>12&&hour<24)
{
printf("Equivalent 12-hour time:%d:%.2d PM",hour-12,fen);
}
else
{
printf("Equivalent 12-hour time:%d:%.2d AM",hour,fen);
}
getch();
}