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Hi all, I got confused by the mock question: int x1 = -1, x2 = -1; x1 = x1 >>> 31; x2 >>= 31; what is the result:

a) x1 = -1, x2 = -1

b) x1 = 1, x2 = -1

c) x1 = 1, x2 = 1

d) x1 = 1, x2 = 0 I think none of is correct. x1=1 is correct, but x2 is not possiable to be -1, 1 or 0. For x2>>=31, the result should be 32 bits with all 1, Am I right? Please help me! mike

Anonymous
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Joined: Nov 22, 2008
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I think the answer is B. The >>> is unsigned and the >> is signed.

x1 is 11111111111111111111111111111111 (32 1's ) x2 is 11111111111111111111111111111111 (32 1's ) x1 = x1 >>>31 x2 >>= 31; now: x1 = 00000000000000000000000000000001 x2 = 11111111111111111111111111111111 >>> adds o's to left. >> adds what was already at the most significatnt bit(1's in our case) M I right?