Secretly Organized Tactical Infantry Exercises (SORTIE) take place in the Błędowska Desert. The main part of the SORTIE shall be the disarmament of a bomb, hidden in an unknown location in the desert.
The first part of the manoeuvres is an airborne operation. The commandos jump individually, in a predetermined order, from a helicopter hovering above the desert. Upon landing, each commando digs in and moves no further. Only then does the next commando proceed.
There is a survival radius defined for each commando. If the distance between the commando and the bomb is equal to (or smaller then) the survival radius, the commando will perish should the bomb go off. The command wants to minimize the number of soldiers taking part in the operation, but it wants to be sure that at least one of them survives the possible explosion.
We shall assume for our purposes that the Błędowska Desert is a plain and we shall identify the positions of the dug in commandos with points on this plane. We are given a sequence of commandos to jump. None of them may miss his turn, i.e. if the i-th commando jumps from the helicopter, than all those before him have already jumped. For each of the commandos we know his survival radius and the coordinates of the point he is going to land in, should he be required to jump.
5 2 2 4 7 2 3 4 3 1 5 7 1 8 7 1the correct outcome is:
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