#include <stdio.h>
#include <stdlib.h>


//define the functions here (simply copy the first line of your function)
int doSubtraction(int a, int b);
float getSlope(int x, int y, int x2, int y2);


void main()
{
     float slope;
     int difference;
     
     printf("main function\n");
     slope = getSlope(2, 5, 4, 10);
     difference = doSubtraction(1, 2);
     printf("difference = %d\n", difference);
     printf("slope = %f\n", slope);
     
     
     system("pause");
}

/*function name suggests the purpose of the function.
 *int at the beginning means the result of using the function should be an integer
 *int a and int b define the arguments to the function; you may guess the function
 *    computes the difference between a and b
 */
int doSubtraction(int a, int b)
{
      return a-b;  //returning an integer
}


/*  function name suggests the purpose of the function.
 * float at the beginning means the result of using this function should be a float
 * int x, int y, int x2, int y2 define the arguments to the function
 *     note: the result of calling a function is usually based on these arguments
 * This function will compute the slope between two points
 */
float getSlope(int x, int y, int x2, int y2)
{
     int difference;
     
     //you can call functions from other functions
     //difference = doSubtraction(2, 3);
     
     float result = (1.0*x2-x)/(1.0*y2-y);
     return result;
}