Sizeof data types

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November 6th, 2012, 10:54 PM

shilpac

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Sizeof data types

I am getting output for below code as 8 4 4 in gcc version 4.5.2. Can anyone explain why I am getting this output ?

Code:

#include<stdio.h>
int main()
{
    printf("%d\t",sizeof(6.5));
    printf("%d\t",sizeof(90000));
    printf("%d",sizeof('A'));
    return 0;
}

November 6th, 2012, 11:48 PM

E-Oreo

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Because on your system, a floating point number is 8 bytes, an integer is 4 bytes, and a character is 4 bytes.

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November 7th, 2012, 12:24 AM

shilpac

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Quote:

Originally Posted by E-Oreo

Because on your system, a floating point number is 8 bytes, an integer is 4 bytes, and a character is 4 bytes.

How can integer and char can take same byte size ?

I guess I found the answer. In sizeof('A'), 'A' is replaced by 65 and sizeof(65) which is integer and that's how it shows 4. Not very sure though.

November 7th, 2012, 01:28 AM

salem

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> printf("%d",sizeof('A'));
In C, character constants are integers, but in C++, character constants are chars.

If you compiled this as a C++ program, you would most likely see 8 4 1 as the output.

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November 7th, 2012, 04:31 AM

shilpac

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Quote:

Originally Posted by salem

> printf("%d",sizeof('A'));
In C, character constants are integers, but in C++, character constants are chars.

If you compiled this as a C++ program, you would most likely see 8 4 1 as the output.

Thank you.