This is a program I saw in Jarowski's book class Sub { public static void main(String ards[]) { int x = 0; boolean b1, b2, b3, b4; b1 = b2 = b3 = b4 = true;

x = ( b1 | b2 & b3 ^ b4) ? x++ : --x; System.out.print(x); } } The o/p is 0(zero). Can anybody pls explain me why ?

x = (b1|b2&b3^4) ? x++ : --x; The expression can be solved in the following manner: Using the following operator preceence: 1> & AND 2> ^ XOR 3> | OR x = (true | ( true & true ) ^ true) ----- 1 x = (true | (true ^ true ) ) -------------2 x = (true | false) -----------------------3 x = true x evaluates to true so the answer is 0. Please correct if I am wrong! Regards, Milind

shatabdi
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Joined: Feb 11, 2000
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Hi Milind, The expression x = (b1|b2&b3^b4) ? x++ : --x; means if(b1|b2&b3^b4) x = x++; else x = --x; System.out.print(x) Now the boolean codn (b1|b2&b3^b4) returns true. So x = x++ should execute. My question is then x should be 1 instead of zero(because of x++)in the o/p. I just don't know why it is showing zero ! shatabdi

See this line CAREFULLY. x=x++; //x = 0[1] which means the LHS is assigned a value 0 which is happened to be x itself. x is incremented and then again assigned to the pre-increment value.

shatabdi
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Joined: Feb 11, 2000
Posts: 6

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Thanks Maha Anna.

Don't get me started about those stupid light bulbs.