expression in condition

[giriembedded]

Hi go through the following code...

void main()
{
          if(~0 == (unsigned int)-1)
           printf("Helloworld");

}

When executing the above program, the printf() is executing.


Explain how we are getting that, and what "(unsigned int)" returns.


Regards
Giri C

[laserlight]

What do you think is the answer?

[giriembedded]

Hi,


The string "Hello World" is get printed on the screen

[laserlight]

No, I am not asking for the output. I am asking you to venture an answer to this:

Explain how we are getting that, and what "(unsigned int)" returns.

[giriembedded]

For me

"unsigned int" is a data type(keyword) which is used to allocate memory to store unsigned int value.

I am in confusion that how we can use it in a expression

[laserlight]

Ah. What you are looking at is a type cast. The result of the expression (unsigned int)-1 is a value with type unsigned int and a value equal to -1 converted to unsigned int, which is equal to UINT_MAX, according to the conversion rules.

[nonoob]

What you are looking for is to explain binary negate ( '~') and two's complement representation for negative 1.