/*

  Sandra N. Kardaras-Flick
  02/15/05
  
STRUCTS

Calculates elapsed time based on user input.

*/

#include<stdio.h>

/*struct for start time*/
typedef struct{int hr; int min; int sec;}START;

/*struct for end time*/
typedef struct{int hr, min, sec;}END;

/*Function prototype*/
void elapsedTime(START s, END t);

main(){

START_s; END_t;

/*value for do-while loop*/
char repeat='y';

/*DO-WHILE loop with sentinel value*/
do{

/*Prompt the user for input*/
printf("\nSTART TIME:\t(use HH MM SS format)\n\n");
scanf("%d %d %d",&s.hr, &s.min, &s.sec);

/*Prompt the user for input*/
printf("\nEND TIME:\t(use SS format)\n\n");
scanf("%d %d %d",&t.hr, &t.min, &t.sec);

/*Function call*/
elapsedTime(s,t);

/*Prompt user to continue, or to quit*/
printf("\nEnter y to continue, or any other key to quit.\n");
scanf(" %c",&repeat);

/*end do-while loop*/
}while (repeat=='y'||repeat=='Y');

return;
}/*end main*/

/*Function Definition*/
void elapsedTime(START s,END t){

/*local variables*/
int durationH, durationM, durationS;

/*Calculate duration*/
durationH=(t.hr-s.hr); durationM=(t.min-s.min);durationS=(t.sec-s.sec);

printf("\nThe elapsed time is: %d Hours, %d Minutes, and %d Seconds\n",durationH, durationM, durationS);

}/*end definition*/

32. 	/*Sandra N. Kardaras-Flick CH 12, Ex. 26*/
#include<stdio.h>

/*struct for start time*/
typedef struct{int x; int y;}POINT;

/*Function prototype*/
void plane(POINT x, POINT y);

main(){

POINT x; POINT y;

/*value for do-while loop*/
char repeat='y';

/*DO-WHILE loop with sentinel value*/
do{

/*Prompt the user for input*/
printf("\nCOORDINATE 1:\t(enter the x value)\n\n");
scanf("%d",&x.x);

/*Prompt the user for input*/
printf("\nCOORDINATE 2:\t(enter the y value)\n\n");
scanf("%d",&y.y);

/*Function call*/
plane(x,y);

/*Prompt user to continue, or to quit*/
printf("\nEnter y to continue, or any other key to quit.\n");
scanf(" %c",&repeat);

/*end do-while loop*/
}while (repeat=='y'||repeat=='Y');

return;
}/*end main*/

/*Function Definition*/
void plane(POINT x, POINT y){

/*local variables*/
int quadrant;

/*Calculate duration*/
if (x.x>0&&y.y>0){quadrant=1;}
if (x.x<0&&y.y>0){quadrant=2;}
if (x.x<0&&y.y<0){quadrant=3;}
if (x.x>0&&y.y<0){quadrant=4;}

printf("\nThe point is in quadrant %d",quadrant);
}