Mixed Integer Nonlinear Programming

An electronic watch having a multiple of modes includes mode selection means operable from the outside and a plurality of external operating buttons for modifying the contents of indication of the watch or for issuing an operational command in each mode. Auxiliary indication means is provided directly with the mode selection means. Alternatively, the auxiliary indication means may be provided separately from the mode selection means but in an interlocked fashion with it. The indication surface of the auxiliary indication means carries at a position corresponding to each of the external operating buttons a symbol or characters which represent the function of said each of the external operating buttons in each selected mode.