Здравствуйте, 7C, Вы писали:

7C>Я всю жизнь считал, что тип определяется первым операндом умножения (и деления), т.е. тип a*z должен быть long!
Это неверно. Тип выражения определяется типом "максимального" операнда, и при этом совершенно неважно, на каком месте в выражении он находится.

5/9
Many binary operators that expect operands of arithmetic or enumeration type cause conversions and yield
result types in a similar way. The purpose is to yield a common type, which is also the type of the result.
This pattern is called the usual arithmetic conversions, which are defined as follows:
— If either operand is of type long double, the other shall be converted to long double.
— Otherwise, if either operand is double, the other shall be converted to double.
— Otherwise, if either operand is float, the other shall be converted to float.
— Otherwise, the integral promotions (4.5) shall be performed on both operands.54)
— Then, if either operand is unsigned long the other shall be converted to unsigned long.
— Otherwise, if one operand is a long int and the other unsigned int, then if a long int can represent
all the values of an unsigned int, the unsigned int shall be converted to a long int;
otherwise both operands shall be converted to unsigned long int.
— Otherwise, if either operand is long, the other shall be converted to long.
— Otherwise, if either operand is unsigned, the other shall be converted to unsigned.
[Note: otherwise, the only remaining case is that both operands are int ]