Hi
Martin beat me to a reply.
Attached is a far less elegant example, which I hope sort of explains the "thought".
In this:-
We have three Counters 1 - 3. These increment at 75Hz
We have three Switch states 1-3, Status of the three switches
We have three Trigger states 1 - 3. These indicate if the Switch has been triggered / already triggered.
We have a main loop.
Before the loop we enable a Timer (75Hz). In the ISR we increment three counters (Count1 / Count2 / Count3)
In the Main loop we test for each switch being active.
If Switch1 is active AND Trigger 1 is inactive we branch
When we branch we reset Counter1 and set Trigger 1 as active
Later we test Counter 1 to be a value (multiples of 75 for each second) and if the value is reached (or exceeded) AND Trigger 1 is active we branch to illuminate the LED.
We use Trigger 1 variable to both Stop multiple resets of the counter and also to stop the counter illuminating the LED if the switch hasn't been triggered,
Same for 2 and 3
Clearly not a finished product but hopefully explains the thought behind it. Many ways to do as you are after so maybe this and Martin's will give you some ideas. Martin's will be better than mine for sure....
Regards