#include <stdio.h>

float read_faren() {
        float value;
        printf("What is the farenheight value? ");
        scanf("%f",&value);
        return value;
        }

float ftoc(float inval) {
        /* For this demo, I have chosen to use a different
        name than the name in the calling function as it helps
        newcomers appreciate how paramaters work. However, it
        could (just happen to) be the same name as in the
        calling code */
        float outval;
        /* * and / happen BEFORE + and - unless you add in
        brackets to change the order [[Bodmas]] */
        outval = (inval - 32.0 ) / 9.0 * 5.0;
        return outval;
        }

void write_cent(float cent_value) {
        /* Demo to show this is another variable of the
        same name as one in another function! */
        printf("%.2f Deg C",cent_value);
        }

void write_far(float value) {
        /* void means "doesn't return anything" */
        printf("%.2f Deg F",value);
        }

void present_results (float faren_value, float cent_value) {
        printf("Farenheight: ");
        write_far(faren_value);
        printf(" converts to ");
        write_cent(cent_value);
        printf("\n");
        }

void report_state(float fval) {
        if (fval < 0.0) {
                printf("Solid\n");
                }
        else if (fval > 100.0) {
                printf("Gas\n");
                }
        else {
                printf("Liquid\n");
                }
        }

main () {

        /* Convert a temperature in Farengrade to Centiheight
        (Yes, I know that's a silly comment). A sample program
        to show good use of strucure and to emphasise the need
        for good variable names and comments too */

        float faren_value;
        float cent_value;

        faren_value = read_faren();
        cent_value = ftoc(faren_value);
        present_results(faren_value, cent_value);
        report_state(cent_value);
        }

/* Sample Output

munchkin:cjul grahamellis$ ./tconv
What is the farenheight value? 44
Farenheight: 44.00 Deg F converts to 6.67 Deg C
Liquid
munchkin:cjul grahamellis$ ./tconv
What is the farenheight value? 4
Farenheight: 4.00 Deg F converts to -15.56 Deg C
Solid
munchkin:cjul grahamellis$ ./tconv
What is the farenheight value? 444
Farenheight: 444.00 Deg F converts to 228.89 Deg C
Gas
munchkin:cjul grahamellis$

*/