bit manipulation - Bit twiddling to get sign bit of 32 bit int -


i convert

(n < 0 ? 1 : 0)

into bit twiddling (assuming 2s complement arch).

for performance reasons.

with unsigned shift,

x = n >>> 31; // java's unsigned shift  x = (int)((uint)n >> 31); // c#'s unsigned shift, casts nop

gcc automatically, other compilers may also. or not. mileage may vary.


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