Hello,
In this code, I got that dgets 0 value but one point Im in trouble. Even a and c is incremented, why wasnt b incremented like them?
Code:#include <stdio.h>int main (void) { int a=0, b=0, c=0, d; d = a++ && b++ || c++; printf("%d%d%d%d", a, b, c, d); } output is 1010.
Line 4 doesn't make sense, I think what you're trying to do is
In line 4 you're basically sayingCode:a++; b++; c++; if(something) d = (a+b); else d = c;
Also I find it easier to separate #include <stdio.h> and int main() with newlines, i think it's a convention in CCode:d = (a++) AND (b++) OR (c++)
First let's put the implied parentheses of operator precedence in
d = ( a++ && b++ ) || c++;
The next thing you need to understand is the short-circuit evaluation of the boolean operators && and ||
Recall that for &&, if the left hand side is false, the right hand side is NOT evaluated.
So in a++ && b++, a is 0 (false), but the side effect of a++ happens (making a=1)
However, since the left hand side of the && is false, b++ doesn't happen.
So now we have ( false ) || c++
The same logic applies to || as well, the right hand side of || is only evaluated if the left hand side is false (which it is).
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
