Created
May 30, 2018 22:22
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Simple C# class to calculate Cantor's pairing function
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using System; | |
public static class CantorPairUtility { | |
public static int CantorPair(int x, int y) { | |
return (((x + y) * (x + y + 1)) / 2) + y; | |
} | |
public static void ReverseCantorPair(int cantor, out int x, out int y) { | |
var t = (int) Math.Floor((-1 + Math.Sqrt(1 + 8 * cantor)) / 2); | |
x = t * (t + 3) / 2 - cantor; | |
y = cantor - t * (t + 1) / 2; | |
} | |
public static int SignedCantorPair(int x, int y) { | |
x = x >= 0 ? 2 * x : -2 * x + 1; | |
y = y >= 0 ? 2 * y : -2 * y + 1; | |
return (((x + y) * (x + y + 1)) / 2) + y; | |
} | |
public static void SignedReverseCantorPair(int cantor, out int x, out int y) { | |
var t = (int) Math.Floor((-1 + Math.Sqrt(1 + 8 * cantor)) / 2); | |
x = t * (t + 3) / 2 - cantor; | |
y = cantor - t * (t + 1) / 2; | |
x = x % 2 == 0 ? x / 2 : ((1 - x) / 2); | |
y = y % 2 == 0 ? y / 2 : ((1 - y) / 2); | |
} | |
} |
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