initial commit

shuffle.py

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+#!/usr/bin/env python3.11
+import random
+
+# Here is an example of an orderd playlist with the artists of the songs.
+# Some artists have more songs in the playlist than others, and currently
+# they're all grouped together
+examplePlaylist: list[str] = [
+  "Artist A", "Artist B", "Artist B", "Artist C", "Artist D", "Artist E", "Artist E", "Artist E", "Artist E",
+  "Artist F", "Artist F", "Artist F", "Artist G", "Artist H", "Artist H", "Artist I", "Artist J", "Artist J", 
+]
+
+# This method to shuffle selects one item randomly and then appends it to a new list
+# This method is not effective, when one item in an array appears more frequently, it
+# is more likely to be picked in a row and will appear in a sequence with itself in the
+# 'shuffled' list.
+def shuffle_one(pl: list[str]) -> list[str]:
+  s: list = []
+  for _ in range(len(pl)):
+    i = pl[random.randint(0, len(pl)) - 1]
+    pl.remove(i)
+    s.append(i)
+  return s
+
+# This algorithm is much better, it applies randomness to every element, selecting a random
+# spot to shuffle with every time, this enables items previously shuffled to once again be
+# shuffles to make a seemingly more 'random' shuffle.
+def shuffle_two(pl: list[str]) -> list[str]:
+  for i in range(len(pl)):
+    swap_idx = random.randrange(i, len(pl))
+    pl[i], pl[swap_idx] = pl[swap_idx], pl[i]
+  return pl
+
+def main() -> None:
+  print(shuffle_one(list(examplePlaylist)))
+  print(shuffle_two(list(examplePlaylist)))
+
+if __name__ == '__main__':
+  main()