Why Does the Answer to "int i=x<y<z;" Equal "1"?

[pairofstrings]

Why is the answer "1"?

Here is a program :

#include<stdio.h>
#include<conio.h>
void main()
{
int i,x=10,y=20,z=5;
clrscr();
i=x<y<z;
printf("%d\n",i);
getch();
}

I am getting the answer as "1". Why? Isn't this suppose to give garbage value if not "0" (zero). Also, please tell me the cases when the answer could be a garbage value or a zero. Please give simple examples. And can you tell me why clrscr(); syntax has to be typed after integer (int) declaration? - Or else it will give you an error.
Thank you very much.

 

[I like Serena]

Hi pairofstrings!

The expression evaluated: i = x < y < z
is not really a proper expression.

It is evaluated as: i = ((x < y) < z);
Since (x < y) is true, this evaluates as: i = (true < z).
Next true is interpreted as "1", so this evaluates as: i = (1 < z);
Again (1 < z) is true, so the value stored in the integer i is "1".

The clrscr() is a non-standard function call that is not necessary.
Its function is to clear the screen.

If you had just declared i without giving it a value, it would have been displayed as garbage.

 

[pairofstrings]

i = ((x < y) < z);
Since (x < y) is true, this evaluates as: i = (true < z).
Next true is interpreted as "1", so this evaluates as: i = (1 < z);
Again (1 < z) is true, so the value stored in the integer i is "1".

What happens when (x<y) is false. Is this interpreted as "0" and this is evaluated as i=(0< z);
then ( 0< z)which is true here since z=5. Now the value of "i" stored is "1" again. Am I right here?

And if I declared i= nothing and then give a print statement then the value is displayed as garbage?

#include<stdio.h>
#include<conio.h>
void main()
{
int i,x=10,y=20,z=5;
clrscr();
printf("%d\n",i);
getch();
}
Will this return a garbage value?

 

[Borek]

What happens when (x<y) is false. Is this interpreted as "0" and this is evaluated as i=(0< z);
then ( 0< z)which is true here since z=5. Now the value of "i" stored is "1" again. Am I right here?

Yes.

Will this return a garbage value?

In general - yes.