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class Integer
require 'backports/tools/arguments'
require 'backports/2.1.0/bignum/bit_length'
require 'backports/2.1.0/fixnum/bit_length'
def self.sqrt(n)
n = Backports.coerce_to_int(n)
return Math.sqrt(n).to_i if n <= 9_999_899_999_899_999_322_536_673_279
bits_shift = n.bit_length / 2 + 1
bitn_mask = root = 1 << bits_shift
loop do
root ^= bitn_mask if (root * root) > n
bitn_mask >>= 1
return root if bitn_mask == 0
root |= bitn_mask
end
end
end unless Integer.respond_to? :sqrt
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