C++ quiz. Are the following operators valid? If they are, wh

Are the following operators valid? If they are, what will be the values of the variables x and y?

int x = (1,024); // --1--
int y;
y = 1,024; // --2--

x = 1
x = 24
x = 20
compilation error in line 1, attempt to assign float value to int variable
compilation error in line 2, syntax error while using assignment operator
compilation error in line 2, attempt to assign float value to int variable
y = 1
y = 20

Explanation

The first statement consists of two expressions, separated by a comma operator. The value of the whole expression is the value of the right expression 024, 20 in the octal notation.
The second statement is also correct, but due to the priority of operations it will execute only assignment operation: (y = 1), 024; The last value is not used.