– Looping [ while ]

If you want to make your computer or robot do something over and over, you use looping functions.

The “while” loop will make your computer repeat a task as long as a certain condition remains true.

For instance, we could think of the game “Red-Light/Green-Light” –

The runners have to stay still until the person at the end of the line says, “Green-Light,” so while the light is green, the runners can run.

Assuming two tasks: ‘runners_run’ and ‘runners_stop’, we could write the “while” part kind of like this:

while (Green_Light)

{

runners_run();

}

runners_stop();

This could be called “pseudo code”, where each task, or function would be further clarified with code statements, such as a call to output a signal to ‘go’ or ‘stop’.

Everything within the {} will loop – or repeat over and over while the light is green. And when the light is no longer green, the program executes the next step.

NEXT: Finite Loops

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One thought on “– Looping [ while ]

  1. Terry Grant

    Another common use example is to wait – for a user input or an external event, like “wait for the starting light”:
    while (red_light) {runners_stay();}
    runners_start_race();

    or “wait for start button”:
    printf(“Press Start!”);
    while(start_button()==0) {} //do nothing but wait
    begin_race();

    Reply

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