How Negative values are stored in system ????

How Negative values are stored in system ????

int a = -1;
printf("Value of a:%x",a );

what will be the result ??? Can you tell me the value of it ???

Is it possible to predict this value ??


Result is:

 Value of a:0xffff ffff

Yes it is possible to predict the value of it.

Reasoning:
 
   Every bit is on or off / binary coded system. In binary coded system,
the negative values can be represented in two ways:

   1.One's complement [convert the zeroes to ones and ones to zeroes]
   2.Two's complement [ Two complement = one's complement value + 1]   


                      value of  1: 0000 0001
 One's complement to represent -1: 1111 1110 [changing the zeroes and to 1s and ones to zeroes in 0000 0001]
 Two's complement value          : 1111 1111 [1111 1110 +1]   

 To represent -1, the values will be stored as 1111 1111  in memory.



In my system, size(int) is 4 bytes.
   
To represent value 1 in Hex: 0x00000001 [ single value represents 4 bits].
         Value 1 in binary  : 00000000 00000000 00000000 00000001
One's complement for -1 in binary: 11111111 11111111 11111111 11111110
       
Two's complement for -1 in binary: 11111111 11111111 11111111 11111111
Two's complement for -1 in Hex   : 0x ffff ffff [single digit represents 4 binary digits]

In the same way, we can try for different negative values too.


int a = -1;
printf("Value of a:%x",a );

what will be the result ??? Can you tell me the value of it ???

Is it possible to predict this value ??


Result is:

 Value of a:0xffff ffff

Yes it is possible to predict the value of it.

Reasoning:
 
   Every bit is on or off / binary coded system. In binary coded system,
the negative values can be represented in two ways:

   1.One's complement [convert the zeroes to ones and ones to zeroes]
   2.Two's complement [ Two complement = one's complement value + 1]   


                      value of  1: 0000 0001
 One's complement to represent -1: 1111 1110 [changing the zeroes and to 1s and ones to zeroes in 0000 0001]
 Two's complement value          : 1111 1111 [1111 1110 +1]   

 To represent -1, the values will be stored as 1111 1111  in memory.



In my system, size(int) is 4 bytes.
   
To represent value 1 in Hex: 0x00000001 [ single value represents 4 bits].
         Value 1 in binary  : 00000000 00000000 00000000 00000001
One's complement for -1 in binary: 11111111 11111111 11111111 11111110
       
Two's complement for -1 in binary: 11111111 11111111 11111111 11111111
Two's complement for -1 in Hex   : 0x ffff ffff [single digit represents 4 binary digits]

In the same way, we can try for different negative values too.