SOLUTION: Taking an algorithm course and working a union-find problem. Algebra & trig too long ago (high school in 1970s) to remember how to calculate permutations. If I have N objects how
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Question 1172654: Taking an algorithm course and working a union-find problem. Algebra & trig too long ago (high school in 1970s) to remember how to calculate permutations. If I have N objects how many union operations do I need for each object to paired with every other object in the set? I looked at permutation and combination formulas and do not understand the ! symbol. Answer by ikleyn(52776) (Show Source):
From your post, I do not understand clearly the exact meaning of the problem.
So, I only can/may guess.
If you need to find the number of pairs, which you can create using n objects,
then the answers are as follow:
a) if we combine different objects in pairs and if the order is important,
then the number of pairs is N*(N-1) (permutations).
b) if we combine different objects in pairs and if the order is NOT important,
then the number of pairs is (combinations).
