Factorial Case with Partial Applications
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combination = -> (n) do
->(r) do
n_factorial = 1
r_factorial = 1
n_r_factorial = 1
for i in 0..n-1
n_factorial*=(n-i)
end
for i in 0..r-1
r_factorial*=(r-i)
end
for i in 0..(n-r)-1
n_r_factorial*=((n-r)-i)
end
combinations = n_factorial/(r_factorial*(n_r_factorial))
return combinations
end
end
n = 10
r = 7
nCr = combination.(n)
puts nCr.(r)
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