SuperMarioLang, 2 bytes
:%
A simple answer in SuperMarioLang. The only command that gets executed is :
which prints the value of the currently pointed memory position (0) as a number (initially 0). The second command %
never gets executed as Mario (the command pointer) falls because there is no floor under him, so the program stops. The average between :
and %
is 0
.
Also works in MarioLANG, where %
is just interpreted as a comment.