please can anyone explain to me why we use combinations in such problems like problem D ?!
thanks in advance and happy new year :-)
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please can anyone explain to me why we use combinations in such problems like problem D ?!
thanks in advance and happy new year :-)
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Otherwise you cannot calculate the answer. No of triplets=n*(n-1)*(n-2) and n<=10^5. This means roughly 10^15 triplets which cannot be calculated individually. So you have to use combinations to generate the answer.
thank you for replying ... i can see why now :-)
Offtopic in first edit.
Also Happy New Year! =)
WTF???:D
http://codeforces.net/settings/rank
There it is. Thought it was bug =)
And me too :D
why it was offTopic??
UPD: never mind
Your Handle seems to be a new year present :P
yeah xD ... I see you got your present too :')
Happy New Year xD