When you enter a model in the command-line interface, you must first specify to LINGO that you are ready to begin entering the LINGO statements. This is done by entering the MODEL: command at the colon prompt. LINGO will then give you a question mark prompt and you begin entering the model line by line.

As an example, we will use the CompuQuick model discussed in the previous section. After entering the CompuQuick model, your screen should resemble the following (note that user input is in bold):

: MODEL:

? MAX = 100 * STANDARD + 150 * TURBO;

? STANDARD <= 100;

? TURBO <= 120;

? STANDARD + 2 * TURBO <= 160;

? END

:

The END command tells LINGO you are finished inputting the model. Once you enter the END command and return to the colon prompt, the model is in memory and ready to be solved.