PROGRAMMING

When you 'OR' 2 char literals, the chars are first converted to their unicode values.

In the case of 'a', 'b' and 'c', these unicode values are 97, 98 and 99 respectively.

The least significant byte of these values in binary is:

97 -> 01100001

98 -> 01100010

99 -> 01100011

It's now easy to see that 'a' | 'b' is 01100011 and if you then OR this result with 'c', you also get 01100011 or 99 decimal.

Converting 99 back to a character gives 'c'.

Consequently, following through the 'switch' statement, the output of that code is:

case D | case d