Secret santa script

README.md

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+# Secret Santa
+
+Example usage:
+
+```
+$ ./secret-santa.py Elsa Anna Kristoffer Svein Olaf
+Svein -> Elsa
+Elsa -> Olaf
+Olaf -> Kristoffer
+Kristoffer -> Anna
+Anna -> Svein
+```

secret-santa.py

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+#!/usr/bin/env python3
+import sys
+import random
+
+rng = random.SystemRandom()
+
+def secret_santa(names):
+    """Draw pairings for secret santa.
+
+    We recognize the problem as a random Hamiltonian cycle
+    on the complete graph formed by the set of names.
+    """
+    g = list(names)
+    rng.shuffle(g)
+    return list(zip(g, g[1:] + g[:1]))
+
+if __name__ == '__main__':
+    for pair in secret_santa(sys.argv[1:]):
+        print("%s -> %s" % pair)