Two rotten oranges sit on opposite sides of a grid. Fresh oranges fill the middle. Both start rotting at minute 0. When does the last fresh orange rot?
Your instinct says to process them one at a time — first all the rot from orange A, then all the rot from orange B. But the oranges rot SIMULTANEOUSLY. Both wavefronts spread from minute 0. Does the order of processing change the answer?
Two rotten oranges start spreading at minute 0. Will processing them one at a time (sequential) give the SAME final time as processing both simultaneously?