Operator != is a binary infix operator: binary because it has two operands and
infix because the operator is written between its operands.

Here is an example:

b != c

Expression b != c evaluates to true only if b and c evaluate to different values;
otherwise, it evaluates to false.

Fill in the values of the "truth table".

For each row, the entry in the column labeled "b != c"
should contain the value of b != c for the values of b and c given to the left.