Thread: Just curious

Once again this is another one of Sams quizes, first here is the question: 10. Write a program that uses a function to find the average of five type float values entered by the user.

Now this is just a very simple example because last time it didn't work so this is like a "start simple and add on to it" kinda things.
Anyways this is my code:

Code:

#include <stdio.h>

float a,b,c,d,e=0;
double f=0;

float average(float,float,float,float,float);

int main(void)
{
	printf("Please enter 5 values: ");
	scanf("%f",&a);
	scanf("%f",&b);
	scanf("%f",&c);
	scanf("%f",&d);
	scanf("%f",&e);

	f=float average(a,b,c,d,e);



	printf("Your values are: %f %f %f %f %f\n\n",a,b,c,d,e);

	return 0;
}

Simple enough right nothing big, no errors, that isn't my question. My questions is why do you have to put spaces to enter your 5 values instead of enter a value hit enter and do that over and over again, I thought that would be wrong so I tried to spread out all of the scaf's into seperate ones but I still have to hit space instead of enter or else the whole thing dies, why is this and how can I change it?

I tried to continue on but this came up: (17) : error C2059: syntax error : 'type'

Now I just updated the code up above to fit my question now, how do I get rid of this type thing and for that matter what is it. My "index" describes it as a syntax error and that I may be missing a closing brace or that the error is in the line above but I simply cannot find it. I thought it would have been simple but I have now tried a few variations of the line that takes the variables(that is the error line)but I just can't get it...any help?

>f=float average(a,b,c,d,e);

your function returns a float but f is a double, and you have 'float' in front of the call to the function, can you do that?

I assume they are trying to typecast this. If so, this is what you want:

f = (float) avarage( a, b, c, d, e );

On a side note, you, the original poster, never actually use the variable 'f', so what's the point?

Quzah.

Hobo:

your function returns a float but f is a double, and you have 'float' in front of the call to the function, can you do that?not sure about the scanf thing,
does
scanf("%f%f%f%f%f", &a, &b, &c, &d, &e);
not do what you want?hope this is helpful.

I tried to put them all in one scanf but I think I had commas between the %f's...would that be a problem? I changed the f to a double just to see if that would fix the 'type' error.



Quzah:

I assume they are trying to typecast this. If so, this is what you want:f = (float) avarage( a, b, c, d, e );

On a side note, you, the original poster, never actually use the variable 'f', so what's the point?

Quzah.

Thanks Quzah, I just tried to typecast it your way and it works, I didn't know about having the float in brackets and I realize that I have yet to use f, sorry about that but I posted this before supper and checked after the movie so I am going to go and try everything now but I just wanted to post the latest stuff I had. But now I have used f, and it returns an average and works just fine, thanks and I guess I am on to the next question

scanf("%f",&a);
scanf("%f",&b);
scanf("%f",&c);
scanf("%f",&d);
scanf("%f",&e);
or
scanf("%f%f%f%f%f", &a, &b, &c, &d, &e);
or
scanf("%f %f %f %f %f", &a, &b, &c, &d, &e);

These 3 versions should all work in the same way.

You can either enter one value per line
value<enter>
value<enter>
value<enter>
value<enter>
value<enter>

or like this
value value value value value<enter>

Basically, any white space you type on input (space, tab, newline) is ignored, and any embedded white space in the scanf control string is also ignored. The only time this "ignore all whitespace" rule is ignored is when you have %c or %[ as the conversion format.

But if you have commas in the control string (or anything else for that matter), then you've got to have the same characters in your input

Eg.
scanf( "%f hello %f", &a, &b );

would need input of
123hello456<enter>
or
123 hello<enter>
456<enter>

Ok I am going to try a couple of different ways of scanning so that I can check on the input and see how everything works but thanks for all your help

Code:

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

void average ( float , float ,float ,float ,float );

int main(){
    float num, num1, num2, num3, num4;

    printf( "Enter five numbers:" );
    scanf("%f%f%f%f%f", &num, &num1, &num2, &num3, &num4 );

    average ( num, num1, num2, num3, num4 );

    system ("pause");
    return 0;
}
void average ( float n, float n1,float n2,float n3,float n4 )
{
 float sum, avg;
     sum = n+n1+n2+n3+n4;
     avg = sum/5;
 printf( "The average is %f", avg );
}

Global varaibles are bad programming technique they are faster but they voilate the principles of least privilage its poor programming practice

Global varaibles are bad programming technique they are faster but they voilate the principles of least privilage its poor programming practice

What are the principles of least privilage? And in every program I have seen they all use global variables unless of course the variables are in a function...why do so many books have that and what is a better way to do it?

>>scanf("%f%f%f%f%f", &num, &num1, &num2, &num3, &num4 );
No matter how you enter the data, always check the return code from scanf() to ensure it did what you asked it too.