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simple question

 
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can someone tell me how do i get the corresponding int value of this
1111111 111111111 11111111 11111010
-Thanks
 
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you know 1111....1111 (32 1's) is -1, right?
then,
-2: 1111....1110
-3: 1111....1101
-4: 1111....1100
-5: 1111....1011
-6: 1111....1010
 
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That way works. But you can also remember that negative nubers are stored in two's compliment form. To find the value of a signed binary number with a negative sign, take the compliment of the number and add one. (The compliment means, make all the 1's zero, and make all the 0's one)
so the two's compliment of
1111111 111111111 11111111 11111010
is
00000000 00000000 00000000 00000101
adding one makes it
00000000 00000000 00000000 00000110
This is 6 in decimal. The number was originally negative, so we know this is a minus-6.
Rob
 
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first look at it: MSB is 1. ok so it got to be a negative number.
second all negative numbers are represented by 2's complement
how to recover a number from 2's complement:
invert all bits (make 1 into 0 and 0 to 1)
and add one
that's it.
111...............1010
invert it---> 00000....0101
add 1-------> 00000....0110 which is 6
we know it was negative so answer is -6

Originally posted by Arsho, Ayan:
can someone tell me how do i get the corresponding int value of this
1111111 111111111 11111111 11111010
-Thanks

 
Consider Paul's rocket mass heater.
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