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Range of int
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Unsigned char is 1 byte long..
it's range is from -128 to 127
Most significant bit is sign bit to indicate whether the char has positive or negative value and the rest 7 bits are meant for storing the actual value of char... so the max +ve value of char can be 127 as expected but in the -ve side how can it be -128 ???
it's range is from -128 to 127
Most significant bit is sign bit to indicate whether the char has positive or negative value and the rest 7 bits are meant for storing the actual value of char... so the max +ve value of char can be 127 as expected but in the -ve side how can it be -128 ???
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0xFF is the largest value that can be stored in one byte, for signed integers that is 0xFF/2, which is 127.5 (use a calculator if you must). Since you can put 0.5 in a byte, one side is 127 and the other is 128 so that 127+128 = 255 (0xFF).
limits.h contains the upper and lower limits of all numeric data types supported by your compiler.
limits.h contains the upper and lower limits of all numeric data types supported by your compiler.
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The reason that it's -128 and 127 breaks down like this: You have 8 bits. One of them is for sign. That leaves 7 bits for the value, or 128 values. One side is 0 to 127. Since you already have 0, the other half is -1 to -128.
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Thanks for ur reply but there are actually 256 values 127 +128+one zero is also there.....and one more thing I can't understand 7 bits (1111111) can contain maximum of 127 so then how value 0f -128 is stored..
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Read up on how Two's Complement works and hopefully you'll see. It comes down to 0 being counted as a positive number, and 1-127+0 is a total of 128 numbers; there's an equal number of negatives, but since it doesn't include 0, you get 1-128.
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Originally Posted by himanjim 
Unsigned char is 1 byte long..
it's range is from -128 to 127
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Originally Posted by himanjim
Most significant bit is sign bit to indicate whether the char has positive or negative value and the rest 7 bits are meant for storing the actual value of char... so the max +ve value of char can be 127 as expected but in the -ve side how can it be -128 ???
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Originally Posted by himanjim
Unsigned char is 1 byte long..
it's range is from -128 to 127
That said, I seem to recall in some discussions that a char is strictly defined as a single byte (8 bits) by the standard but I'm not sure where to double check that...
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Originally Posted by Infarction
Just noticed... an unsigned char has values 0 to 255, and a signed char is -128 to 127.
That said, I seem to recall in some discussions that a char is strictly defined as a single byte (8 bits) by the standard but I'm not sure where to double check that...
Last edited by Dave Sinkula; Feb 17th, 2007 at 4:30 am.
"One of the methods used by statists to destroy capitalism consists in establishing controls that tie a given industry hand and foot, making it unable to solve its problems, then declaring that freedom has failed and stronger controls are necessary." --Ayn Rand
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Byte is not defined as 8 bits then what is it defined as?
>Byte is not defined as 8 bits then what is it defined as?
It's defined as whatever the implementation wants. The standard only specifies that sizeof ( char ) be 1, and at least 8 bits. That happens to be the most common definition of a byte, but systems other than your PC also support C and don't have the same definition.
It's defined as whatever the implementation wants. The standard only specifies that sizeof ( char ) be 1, and at least 8 bits. That happens to be the most common definition of a byte, but systems other than your PC also support C and don't have the same definition.
I'm here to prove you wrong.
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