This schematic employs 2 multiplexers (2 lines each) to select between Green and Purple input lines (left-most on/off buttons). Both multiplexers are connected to the same set of inputs, but different outputs, therefore allowing the signal from any input to be routed to any output. The outputs are denoted using white light bulbs. The control lines (top and bottom on/off buttons) are per output (top and bottom outputs, respectively).
