59 lines
1.2 KiB
Python
59 lines
1.2 KiB
Python
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#!/usr/bin/env python3
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from math import sqrt
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def main(d):
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mx = 0
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my = 0
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md = 0
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for cd in range(2, d + 1):
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x, y = diop(cd)
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#print("{} -> {}, {}".format(cd, x, y))
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if x > mx:
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mx = x
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my = y
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md = cd
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return md, mx, my
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def diop(d):
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sol = []
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a, f = sq_frac(d)
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f.reverse()
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if len(f) == 0:
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return 0, 0
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for i in f:
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for j in range(len(sol)):
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sol[j][0], sol[j][1] = sol[j][0] * i + sol[j][1], sol[j][0]
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sol.append([i, 1])
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r = fits(a, sol, d)
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while r == 0:
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for i in f:
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for j in range(len(sol)):
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sol[j][0], sol[j][1] = sol[j][0] * i + sol[j][1], sol[j][0]
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r = fits(a, sol, d)
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return r
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def fits(a, pairs, d):
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for x, y in pairs[::-1]:
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x, y = a * x + y, x
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if x**2 - d * y**2 == 1:
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return x, y
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return 0
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def sq_frac(x):
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f = []
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m = int(sqrt(x))
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if m**2 == x:
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return m, f
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d = x - m**2
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f.append((2 * m) // d)
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n = f[-1] * d - m
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while d != 1:
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d = (x - n**2) // d
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f.append((n + m) // d)
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n = f[-1] * d - n
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return m, f
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if __name__ == '__main__':
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print(main(1000)[0])
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