3 ms·

Came here to suggest the function that is 1 on the rationals and 0 on the irrationals.

• adrianhel 7y ago
  Not continuous.
  • throwawaymath 7y ago
    I think that was the point.
  • analog31 7y ago
    Also can't be computed.
    • nightcracker 7y ago
      That depends on the input format.