Submission #169911

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Source Code Expand

n = gets.to_i
c = Array.new(n,0)
count = Array.new(n,-1)
n.times do |i|
    c[i] = gets.to_i
end
c.sort!
sum = 0
v = (1..n).inject(:*)
for i in 0...n
    for j in 0...n
        if c[i]%c[j]==0
            count[i] += 1
        end
    end
end
for i in 0...n
    sum += count[i]%2==1 ? v/2 : v*(count[i]+2)/(2*count[i]+2)
end
p sum.to_f/v.to_f

Submission Info

Judge Result