Day 6 - Functions and Modularity

CLASSWORK:
Beehive function
int beehive(double a,double b,double c, double d)
{
int count = 0;
if (a > b)
count ++;
if (b<c)
count ++;
if (d>a)
count ++;
if (a<c)
count ++;
else
count ++;
Return count;
}
HOMEWORK:
Great Circle Distance b/w Two Points in the Northern Hemisphere
/*––––––––––––––––––––â€*/
/*  This program determines the distance between two points    */
/*  that are specified with latitude and longitude values      */
/*  that are in the Northern Hemisphere.                       */
#include <stdio.h>
#include <math.h>
#define PI 3.141593
int main(void)
{
/*  Declare variables and function prototype.  */
double lat1, long1, lat2, long2;
double gc_distance(double lat1,double long1, 
double lat2,double long2);
/*  Get locations of two points.  */
printf("Enter latitude north and longitude west ");
printf("for location 1: \n");
scanf("%lf %lf",&lat1,&long1);
printf("Enter latitude north and longitude west ");
printf("for location 2: \n");
scanf("%lf %lf",&lat2,&long2);
/*  Print great circle distance.  */
printf("Great Circle Distance: %.0f miles \n",
gc_distance(lat1,long1,lat2,long2));
/*  Exit program.  */
return 0;
}
/*–––––––––––––––––––––––*/
/*  This function computes the distance between two            */
/*  points using great circle distances.                       */
double gc_distance(double lat1,double long1, 
double lat2,double long2)
{
/*  Declare variables.  */
double rho, phi, theta, gamma, dot, dist1, dist2,x1, y1, z1, x2, y2, z2;
/*  Convert latitude,longitude to rectangular coordinates.  */
rho = 3960;
phi = (90 - lat1)*(PI/180.0);
theta = (360 - long1)*(PI/180.0);
x1 = rho*sin(phi)*cos(theta);
y1 = rho*sin(phi)*sin(theta);
z1 = rho*cos(phi);
phi = (90 - lat2)*(PI/180.0);
theta = (360 - long2)*(PI/180.0);
x2 = rho*sin(phi)*cos(theta);
y2 = rho*sin(phi)*sin(theta);
z2 = rho*cos(phi);
/*  Compute angle between vectors.  */
dot = x1*x2 + y1*y2 + z1*z2;
dist1 = sqrt(x1*x1 + y1*y1 + z1*z1);
dist2 = sqrt(x2*x2 + y2*y2 + z2*z2);
gamma = acos(dot/(dist1*dist2));
/*  Compute and return great circle distance.  */
return gamma*rho;
}