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copied!<p>After playing a given song, use a pseudo-append to place it near the end of the list. You'll probably want about 1/2 to 2/3 to be truly appended and the other 1/3 to 1/2 spread within the last 5 or so items in the list.</p> <p>Obviously this won't work for very short lists, but should be fine for lists of 10 or more.</p> <hr> <p>Edit (provide more detail about 'PseudoAppend'):</p> <p>The following pseudo-code uses a mix of language constructs but should be easy enough to turn into real code.</p> <p>Given List[songs]</p> <pre><code>While(PLAY) Play(List[0]) PseudoAppend(List[], 0) def PseudoAppend(List[], index) # test to verify length of list, valid index, etc. song = List[index].delete # < not safe List.append(song) target = -1 While( (random() < (1/3)) && (target > -3) ) Swap(List[target], List[target-1]) target -= 1 </code></pre> <p>Removing the just-completed song from the list without first having a backup list can result in information loss, but this is just pseudo-code meant to convey an idea.</p> <p>As you can see, 2/3 of the time the song that was just played will be moved to the back of the list, and 1/3 of the time it will be moved ahead of the last song.</p> <p>Of the 1/3 chance that the song is moved forward, 2/3 of the time it will only be moved ahead of one song, and the other 1/3 of the time it will be moved ahead of two or more songs. Chance that song moves to last position=66%, second to last position=22%, third to last=12%.</p> <p>The actual behavior of the PseudoAppend is all governed within the condition of the <code>While</code> statement. You can change the value to compare against the <code>random</code> number generator to make it more or less likely that a song is moved ahead of others, and you can change the value compared to <code>target</code> to adjust how far the just-completed song can move ahead in the list.</p> <p><hr> Edit II (Python 3 code and sample output for a list of 11 items)</p> <pre><code>songlist=[0,1,2,3,4,5,6,7,8,9,10] import random def pseudoappend(locallist, index): song=locallist[index] del(locallist[index]) locallist.append(song) target=-1 while (random.randint(1,3)==1) and (target> -3): locallist[target],locallist[target-1] = locallist[target-1],locallist[target] target-=1 for x in range(len(songlist)*9): print("%3d" % x, ': ', "%2d" % songlist[0], ': ', songlist) pseudoappend(songlist, 0) print( 'end : ', "%2d" % songlist[0], ': ', songlist) </code></pre> <p>Here's a sample output running through the list ~9 times. The first column is simply a running index, the second column shows the currently selected song, and the third column shows the current order of the list:</p> <pre><code>>>> ================================ RESTART ================================ >>> 0 : 0 : [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] 1 : 1 : [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 0] 2 : 2 : [2, 3, 4, 5, 6, 7, 8, 9, 10, 0, 1] 3 : 3 : [3, 4, 5, 6, 7, 8, 9, 10, 0, 1, 2] 4 : 4 : [4, 5, 6, 7, 8, 9, 10, 0, 1, 2, 3] 5 : 5 : [5, 6, 7, 8, 9, 10, 0, 1, 2, 3, 4] 6 : 6 : [6, 7, 8, 9, 10, 0, 1, 2, 3, 4, 5] 7 : 7 : [7, 8, 9, 10, 0, 1, 2, 3, 4, 5, 6] 8 : 8 : [8, 9, 10, 0, 1, 2, 3, 4, 5, 6, 7] 9 : 9 : [9, 10, 0, 1, 2, 3, 4, 5, 6, 7, 8] 10 : 10 : [10, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9] 11 : 0 : [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] 12 : 1 : [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 0] 13 : 2 : [2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 0] 14 : 3 : [3, 4, 5, 6, 7, 8, 9, 10, 1, 0, 2] 15 : 4 : [4, 5, 6, 7, 8, 9, 10, 1, 0, 2, 3] 16 : 5 : [5, 6, 7, 8, 9, 10, 1, 0, 2, 3, 4] 17 : 6 : [6, 7, 8, 9, 10, 1, 0, 2, 3, 4, 5] 18 : 7 : [7, 8, 9, 10, 1, 0, 2, 3, 4, 6, 5] 19 : 8 : [8, 9, 10, 1, 0, 2, 3, 4, 6, 7, 5] 20 : 9 : [9, 10, 1, 0, 2, 3, 4, 6, 7, 5, 8] 21 : 10 : [10, 1, 0, 2, 3, 4, 6, 7, 5, 8, 9] 22 : 1 : [1, 0, 2, 3, 4, 6, 7, 5, 10, 8, 9] 23 : 0 : [0, 2, 3, 4, 6, 7, 5, 10, 8, 9, 1] 24 : 2 : [2, 3, 4, 6, 7, 5, 10, 8, 9, 1, 0] 25 : 3 : [3, 4, 6, 7, 5, 10, 8, 9, 2, 1, 0] 26 : 4 : [4, 6, 7, 5, 10, 8, 9, 2, 1, 0, 3] 27 : 6 : [6, 7, 5, 10, 8, 9, 2, 1, 0, 3, 4] 28 : 7 : [7, 5, 10, 8, 9, 2, 1, 0, 3, 4, 6] 29 : 5 : [5, 10, 8, 9, 2, 1, 0, 3, 4, 6, 7] 30 : 10 : [10, 8, 9, 2, 1, 0, 3, 4, 5, 6, 7] 31 : 8 : [8, 9, 2, 1, 0, 3, 4, 5, 10, 6, 7] 32 : 9 : [9, 2, 1, 0, 3, 4, 5, 10, 6, 7, 8] 33 : 2 : [2, 1, 0, 3, 4, 5, 10, 6, 7, 9, 8] 34 : 1 : [1, 0, 3, 4, 5, 10, 6, 7, 9, 8, 2] 35 : 0 : [0, 3, 4, 5, 10, 6, 7, 9, 8, 2, 1] 36 : 3 : [3, 4, 5, 10, 6, 7, 9, 8, 2, 1, 0] 37 : 4 : [4, 5, 10, 6, 7, 9, 8, 2, 1, 0, 3] 38 : 5 : [5, 10, 6, 7, 9, 8, 2, 1, 0, 3, 4] 39 : 10 : [10, 6, 7, 9, 8, 2, 1, 0, 3, 4, 5] 40 : 6 : [6, 7, 9, 8, 2, 1, 0, 3, 4, 5, 10] 41 : 7 : [7, 9, 8, 2, 1, 0, 3, 4, 5, 10, 6] 42 : 9 : [9, 8, 2, 1, 0, 3, 4, 5, 7, 10, 6] 43 : 8 : [8, 2, 1, 0, 3, 4, 5, 7, 10, 6, 9] 44 : 2 : [2, 1, 0, 3, 4, 5, 7, 10, 6, 9, 8] 45 : 1 : [1, 0, 3, 4, 5, 7, 10, 6, 2, 9, 8] 46 : 0 : [0, 3, 4, 5, 7, 10, 6, 2, 9, 8, 1] 47 : 3 : [3, 4, 5, 7, 10, 6, 2, 9, 8, 1, 0] 48 : 4 : [4, 5, 7, 10, 6, 2, 9, 8, 1, 3, 0] 49 : 5 : [5, 7, 10, 6, 2, 9, 8, 1, 3, 0, 4] 50 : 7 : [7, 10, 6, 2, 9, 8, 1, 3, 5, 0, 4] 51 : 10 : [10, 6, 2, 9, 8, 1, 3, 5, 0, 7, 4] 52 : 6 : [6, 2, 9, 8, 1, 3, 5, 0, 7, 4, 10] 53 : 2 : [2, 9, 8, 1, 3, 5, 0, 7, 6, 4, 10] 54 : 9 : [9, 8, 1, 3, 5, 0, 7, 6, 4, 10, 2] 55 : 8 : [8, 1, 3, 5, 0, 7, 6, 4, 10, 2, 9] 56 : 1 : [1, 3, 5, 0, 7, 6, 4, 10, 2, 9, 8] 57 : 3 : [3, 5, 0, 7, 6, 4, 10, 2, 9, 1, 8] 58 : 5 : [5, 0, 7, 6, 4, 10, 2, 9, 3, 1, 8] 59 : 0 : [0, 7, 6, 4, 10, 2, 9, 3, 1, 8, 5] 60 : 7 : [7, 6, 4, 10, 2, 9, 3, 1, 8, 5, 0] 61 : 6 : [6, 4, 10, 2, 9, 3, 1, 8, 5, 0, 7] 62 : 4 : [4, 10, 2, 9, 3, 1, 8, 5, 0, 7, 6] 63 : 10 : [10, 2, 9, 3, 1, 8, 5, 0, 7, 6, 4] 64 : 2 : [2, 9, 3, 1, 8, 5, 0, 7, 6, 4, 10] 65 : 9 : [9, 3, 1, 8, 5, 0, 7, 6, 4, 10, 2] 66 : 3 : [3, 1, 8, 5, 0, 7, 6, 4, 10, 2, 9] 67 : 1 : [1, 8, 5, 0, 7, 6, 4, 10, 2, 9, 3] 68 : 8 : [8, 5, 0, 7, 6, 4, 10, 2, 9, 3, 1] 69 : 5 : [5, 0, 7, 6, 4, 10, 2, 9, 8, 3, 1] 70 : 0 : [0, 7, 6, 4, 10, 2, 9, 8, 3, 1, 5] 71 : 7 : [7, 6, 4, 10, 2, 9, 8, 3, 0, 1, 5] 72 : 6 : [6, 4, 10, 2, 9, 8, 3, 0, 1, 5, 7] 73 : 4 : [4, 10, 2, 9, 8, 3, 0, 1, 5, 7, 6] 74 : 10 : [10, 2, 9, 8, 3, 0, 1, 5, 7, 6, 4] 75 : 2 : [2, 9, 8, 3, 0, 1, 5, 7, 6, 4, 10] 76 : 9 : [9, 8, 3, 0, 1, 5, 7, 6, 4, 10, 2] 77 : 8 : [8, 3, 0, 1, 5, 7, 6, 4, 10, 2, 9] 78 : 3 : [3, 0, 1, 5, 7, 6, 4, 10, 2, 9, 8] 79 : 0 : [0, 1, 5, 7, 6, 4, 10, 2, 3, 9, 8] 80 : 1 : [1, 5, 7, 6, 4, 10, 2, 3, 9, 8, 0] 81 : 5 : [5, 7, 6, 4, 10, 2, 3, 9, 8, 1, 0] 82 : 7 : [7, 6, 4, 10, 2, 3, 9, 8, 1, 0, 5] 83 : 6 : [6, 4, 10, 2, 3, 9, 8, 1, 0, 7, 5] 84 : 4 : [4, 10, 2, 3, 9, 8, 1, 0, 7, 5, 6] 85 : 10 : [10, 2, 3, 9, 8, 1, 0, 7, 5, 6, 4] 86 : 2 : [2, 3, 9, 8, 1, 0, 7, 5, 6, 4, 10] 87 : 3 : [3, 9, 8, 1, 0, 7, 5, 6, 4, 2, 10] 88 : 9 : [9, 8, 1, 0, 7, 5, 6, 4, 2, 10, 3] 89 : 8 : [8, 1, 0, 7, 5, 6, 4, 2, 10, 3, 9] 90 : 1 : [1, 0, 7, 5, 6, 4, 2, 10, 8, 3, 9] 91 : 0 : [0, 7, 5, 6, 4, 2, 10, 8, 3, 1, 9] 92 : 7 : [7, 5, 6, 4, 2, 10, 8, 3, 1, 9, 0] 93 : 5 : [5, 6, 4, 2, 10, 8, 3, 1, 9, 0, 7] 94 : 6 : [6, 4, 2, 10, 8, 3, 1, 9, 0, 7, 5] 95 : 4 : [4, 2, 10, 8, 3, 1, 9, 0, 7, 6, 5] 96 : 2 : [2, 10, 8, 3, 1, 9, 0, 7, 6, 4, 5] 97 : 10 : [10, 8, 3, 1, 9, 0, 7, 6, 4, 5, 2] 98 : 8 : [8, 3, 1, 9, 0, 7, 6, 4, 5, 2, 10] end : 3 : [3, 1, 9, 0, 7, 6, 4, 5, 2, 10, 8] </code></pre>

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