29 lines
565 B
Python
29 lines
565 B
Python
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q = 2**255 - 19
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def expmod(b,e,m):
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if e == 0: return 1
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t = expmod(b,e/2,m)**2 % m
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if e & 1: t = (t*b) % m
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return t
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def inv(x):
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return expmod(x,q-2,q)
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def radix255(x):
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x = x % q
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if x + x > q: x -= q
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x = [x,0,0,0,0,0,0,0,0,0]
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bits = [26,25,26,25,26,25,26,25,26,25]
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for i in range(9):
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carry = (x[i] + 2**(bits[i]-1)) / 2**bits[i]
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x[i] -= carry * 2**bits[i]
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x[i + 1] += carry
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result = ""
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for i in range(9):
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result = result+str(x[i])+","
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result = result+str(x[9])
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return result
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d = -121665 * inv(121666)
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print radix255(d)
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