радвам се, че те развеселявам. все пак виж, какво пишат по стандартите:

Except where noted, the order of evaluation of operands of individual operators and subexpressions of individual
expressions, and the order in which side effects take place, is unspecified. Between the previous and
next sequence point a scalar object shall have its stored value modified at most once by the evaluation of an
expression. Furthermore, the prior value shall be accessed only to determine the value to be stored. The
requirements of this paragraph shall be met for each allowable ordering of the subexpressions of a full
expression; otherwise the behavior is undefined. [Example:
i = v[i++]; // the behavior is undefined
i = 7, i++, i++; // ‘i’ becomes 9
i = ++i + 1; // the behavior is undefined
i = i + 1; // the value of ’i’ is incremented
—end example]