16 lines
277 B
Lua
16 lines
277 B
Lua
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local M = {}
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function M.modinverse(b, m)
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local g, x, _ = M.gcd(b, m)
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if g ~= 1 then return nil end
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return x % m
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end
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function M.gcd(a, b)
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if a == 0 then return b, 0, 1 end
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local g, x1, y1 = M.gcd(b % a, a)
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return g, y1 - (math.floor(b / a)) * x1, x1
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end
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return M
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