loop showing weight loss needed until user is healthy

Conditionals and Loops example from a Well House Consultants training course
More on Conditionals and Loops [link]

Source code: eight.c Module: C203

#include <stdio.h>

/* Every langauge has at least one way of repeating code - loops, and
usually many ways. In C and C++, the most fundamental loop is a while
loop where you prvide a boolean test (in a set of round brackets) and the
code in the single statement, or { } surrounded block, that follows is
repeated until the condition - which is re-evalueated each time around,
becomes false at the start of a new iteration.

You need to do something within your loop to make the condition go false
when you're done, otherwise you end up with a loop that will never exit -
an infinite loop. (You could use a "break" or "return" go get out from
within a loop too, but those are tecniques that should be used with care) */

float getbmi(float w, float h) {
        float bmi;
        bmi = w / (h * h);
        return bmi;
        }

int main () {
        float height,weight;
        float bmi;

/* Get the user's height and weight and claculate his BMI */

        printf("How high are you (metres): ");
        scanf("%f",&height);

        printf("How hefty are you (kilograms): ");
        scanf("%f",&weight);

        bmi = getbmi(weight,height);
        printf ("BMI is %.2f\n",bmi);

/* While his BMI remains over 27.5, keep seeing what effect a drop
in weight of 2 kg will have. In effect, you're providing a table of
weight reduction to a more healthy figure; no matter how heavy the
user of the program starts off, by dropping 2kg at a time he will
eventually hit his target bmi! */

        while (bmi > 27.5) {
                weight -= 2.0;
                bmi = getbmi(weight,height);
                printf ("drop to %.2f and BMI is then %.2f\n",
                                weight, bmi);
                }

        return 0;
        }

/* munchkin:capr grahamellis$ ./eight
How high are you (metres): 1.75
How hefty are you (kilograms): 96
BMI is 31.35
drop to 94.00 and BMI is then 30.69
drop to 92.00 and BMI is then 30.04
drop to 90.00 and BMI is then 29.39
drop to 88.00 and BMI is then 28.73
drop to 86.00 and BMI is then 28.08
drop to 84.00 and BMI is then 27.43
munchkin:capr grahamellis$
*/

Learn about this subject

This module and example are covered on the following public courses:
* Learning to Program in C
* Learning to program in C and C++
* Programming in C
* C and C++ Programming
* Learning to program in C and C++
* C and C++ Programming
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