shift - Bitshifting in C++ producing the wrong answer -

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i tried running following code code:

char c = (2 << 7) >> 7

which should return 0 because 2 has binary representation char:

0 0 0 0 0 0 1 0

after 7 shifts left, 

0 0 0 0 0 0 0 0

then, after 7 shifts right, get

0 0 0 0 0 0 0 0

however, i'm getting result 2, not 0.

the compiler says 2 << 7 256, it's char , shouldn't 256.

i understand 2 << 7 calculated ints , answer put c 256 >> 7 2.

i tried cast 2 char (ex: (char)2>>7) doesn't work either.

i'm trying extract each bit char, wrote code:

char c = 0x02; for(int i=0;i<7;i++) {     char current = (c<<i)>>7; }

how can each bit? what's wrong way?

the result of arithmetic shift operation 1 operand being int in c++ int. therefore, when write

current = (c << i) >> 7;

c++ interpret (c << i) , (c << i) >> 7 ints, casting char when assignment done. since temporary values ints, no overflow occurs , result should come out integer result casted char.

hope helps!


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