>>17
Your definition doesn't really make sense to me:

(((a & b & c) | b | c) == a)

Since a, b, and c are integers, and | is a logical operator,

(((a & b & c) | b | c) 

will always evaluate to TRUE unless a, b, and c are all 0.

here is what tD() would look like in C:

bool tD( int a, int b, int c )
{
    return !( (a == b) || (b == c) || (a == c) )
}