A variable of type int is a general integer, equivalent to an unsigned int. In C++, the value of this expression is 32.

There is a comma expression in brackets. Then assign the value of this comma expression to X.

Comma expression: the form of comma expression is generally: expression 1, expression 2, expression 3 ... The solution process of comma expression is: first solve expression 1, then solve expression 2 ... The value of comma expression is the value of the last expression. So the comma expression here: y = 4, z = 16, and k = 32 has a value of 32.