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Need help in a math problem.

Revision en3, by VastoLorde95, 2015-06-12 12:56:13

Hi, In this problem, I am using the idea that AM >= GM just like in the editorial but with slightly different steps.

Equality should hold when all elements are equal. So according to me, x = y = z and the solution I arrive at is that x = y = z = S / 3

But this is incorrect as seen from the test case

S = 10

a = 1, b = 6, c = 3

My solution gives x = y = z = 3.33 and hence x a·y b·z c =  169350.87

But the optimal solution is x = 1.0, y = 6.0, z = 3.0 with x a·y b·z c =  1259712

What is the flaw in my math? Is this not a correct way to use GM <= AM? I don't understand why my solution differs from the solution given in the editorial even though the principle behind both is the same.

Tags math, codeforces, inequalities, help


  Rev. Lang. By When Δ Comment
en3 English VastoLorde95 2015-06-12 12:56:13 17
en2 English VastoLorde95 2015-06-12 12:53:35 2
en1 English VastoLorde95 2015-06-12 12:51:59 862 Initial revision (published)