c++ - Weird boolean conversion (?) -

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explain pleasy why second expression returns false

   cout << (4==4) << endl; //1    cout << (4==4==4) << endl; // 0

(4==4==4) ((4==4)==4) (true == 4) (1==4) 1 false 2 getting printed 0.

note == has associativity left-to-right, doesn't matter (in this case) because if had associativity right-to-left, result have been same.

1. due integral promotion.
2. note 1 might tempted think 4 in (true==4) treated true (after 4 non-zero, hence true). thinking might conclude (true==4) (true==true) true. not how works. bool gets promoted int, instead of int bool.


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