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enable pairing for large integers (issue #3) #4

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enable pairing for large integers (issue #3) #4

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16 changes: 9 additions & 7 deletions pairing_functions/cantor.py
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Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
# -*- coding: utf-8 -*-

from collections import deque
from math import pow, floor, sqrt
from math import pow, floor, isqrt


def pair(*numbers: int) -> int:
Expand Down Expand Up @@ -51,12 +51,14 @@ def unpair(number: int, n: int = 2) -> tuple:
"""
if (number < 0) or (not isinstance(number, int)):
raise ValueError('Cantor unpairing function requires a non-negative integer')

w = floor((sqrt(8 * number + 1) - 1) / 2)
t = (pow(w, 2) + w) / 2

n2 = int(number - t)
n1 = int(w - n2)

# calculate cantor unpairing using integer square root
m = isqrt(25 * (8 * number + 1))
w = m // 10
if m % 10 < 5: w -= 1
t = (w * w + w) // 2
n2 = number - t
n1 = w - n2

if n > 2:
return unpair(n1, n - 1) + (n2,)
Expand Down
16 changes: 5 additions & 11 deletions pairing_functions/szudzik.py
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Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
# -*- coding: utf-8 -*-

from collections import deque
from math import pow, floor, sqrt
from math import pow, floor, isqrt


def pair(*numbers: int) -> int:
Expand Down Expand Up @@ -55,16 +55,10 @@ def unpair(number: int, n: int = 2) -> tuple:
if (number < 0) or (not isinstance(number, int)):
raise ValueError('Szudzik unpairing function requires a non-negative integer')

if number - pow(floor(sqrt(number)), 2) < floor(sqrt(number)):

n1 = number - pow(floor(sqrt(number)), 2)
n2 = floor(sqrt(number))

else:
n1 = floor(sqrt(number))
n2 = number - pow(floor(sqrt(number)), 2) - floor(sqrt(number))

n1, n2 = int(n1), int(n2)
q = isqrt(number)
l = number - q * q

n1, n2 = (l, q) if l < q else (q, l - q)

if n > 2:
return unpair(n1, n - 1) + (n2,)
Expand Down