Thread: calloc

if i swich the two lines of the code

Code:

return 0;
	free(makeAnArray);

it seems to work. The question that I have is if I am using the right array makeAnArray or is it supposed to be anArray or array or even return?
which one would free the correct array

Returning from the function BEFORE you free the Array doesn't really make much sense. It might "work", but it doesn't do all that you want it to.

Code:

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

double* makeAnArray(double size);

int main (void)
{
	double *anArray;
	char throwaway;
	int size = 0;
	int k;
	
	printf("Please enter the size of the array: ");
	fflush(stdout);
	scanf("&#37;d", &size);
	scanf("%c", &throwaway);

	anArray = makeAnArray(size);

	for (k = 0; k < size; k++)
	{
		printf("%f  ", anArray[k]);
	}
	printf("\n");
	fflush(stdout);
	
	free(anArray);

	getchar();
	
	return 0;
}
double* makeAnArray(double size)
{
	double* array;
	
	array = calloc(size,sizeof(double));
	
	return array;
}

And here's the output:

Code:

Please enter the size of the array: 10
0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000

I'm begging you, look at the red highlights HARD. These are the things you need to study.

what is foo?????

thanks for help
just a quick question
fflush(stdout);
what is this? what does it do?

what is it used for? when do you use it? what is the purpose of it???

Originally Posted by goran00

thanks for help
just a quick question
fflush(stdout);
what is this? what does it do?

It flushes the output buffer. My internal output console sometimes doesn't display my printfs immediately when I want them to. So I call fflush(stdout) to make sure they're output to the screen.

你为什么用double类型的形参来接收int类型的实参的值呢？
You why use double type virtual parameter take-over int type fact parameter?

makeAnArray(double size)

Originally Posted by Elysia

It flushes the output buffer. It forces all the data inside the output buffer to be directed to the screen.
This may or may not be necessary, but it doesn't hurt.

printf("\n"); always flushes the output buffer

Originally Posted by KIBO

printf("\n"); always flushes the output buffer

Sure does. But sometimes you don't want a new line.

Originally Posted by KIBO

printf("\n"); always flushes the output buffer

No. It only flushes the buffer if the stream is configured to line buffering mode. If it's fully buffered, there is no guarantee of a flush.

Granted, when output is going to the screen, the stream is preconfigured into line buffer mode for you.