I'm trying to create a BMI calculator in C programming! I just can't get it to calculate the final result. Everything else runs fine. //Katrina

//5/27/11

//Assignment 1- Part A: BMI Calculator#include <stdio.h>

int main() {

int inches, pounds;

float BMI;

printf("What is your height in inches? \n", inches);

scanf("%d", & inches);

printf("What is your weight in pounds? \n", pounds);

scanf("%d", & pounds);

BMI=((pounds*703)/(inches*inches));

printf("Your BMI is: %.2f \n", BMI);

system:("pause");

return 0;

}

<deleted by nails>

No that's didn't help either. The formula the prof. gives us is BMI=(weight in pounds*703)/(height in inches)^(2) I've tried everything so many different combinations

What's happening is the Output will let me type the height and the weight

and after I press enter after inputting weight the screen will flash for a fraction of a second BMI= (something unreadable)

and then the screen will close.

AAAHHHH

<deleted by nails>

As well as the simple mechanics of the pause and the question over the formula, there is a classic C error in your program. You divide an int by an int and assign the result to a float: BMI=((pounds*703)/(inches*inches));

This will work, due to automatic type coercion, but will give an incorrect result - you will lose the fractional part of the result. The int will be divided by the int and produce an int result, which is then co-erced to a float. For example the code:

int i= 3, j = 4;

float r;r = j/i;

produces the result r = 1.0000..., not r = 1.3333....

You need to cast the ints to floats (or just make them floats in the first place) before doing the division:

BMI=((float)(pounds*703)/(float)(inches*inches));

(Strictly speaking, the first cast would suffice, but it's more elegant to cast both the numerator and the denominator.)

Nails, Unless I'm being really stupid, aren't:

BMI=(pounds/(inches*inches)) * 703;

and

BMI=((pounds*703)/(inches*inches));

exactly the same thing (forgetting for the moment questions of type co-ercion)? As mathematical formulae they are equivalent.

Apologies on my part. this is one thread I should have checked closer.

Got it.

Thanks. 1st time programmer working on something late at night doesn't work so great!

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