p_id | v_id | s_id
  1  |  1   |  1
  2  |  1   |  2
  3  |  1   |  3
  4  |  1   |  4
  1  |  2   |  5
  2  |  2   |  6
  3  |  2   |  7
  4  |  2   |  8
  2  |  3   |  9
  4  |  3   |  10
  1  |  4   |  11
  2  |  4   |  12
  4  |  4   |  13
  3  |  5   |  14

##</code><code>##

     | p_1  | p_2  | p_3  | p_4  |
---------------------------------
 v_1 | s_1  | s_2  | s_3  | s_4  |
 v_2 | s_5  | s_6  | s_7  | s_8  |
 v_3 |      | s_9  |      | s_10 |
 v_4 | s_11 | s_12 |      | s_13 |
 v_5 |      |      | s_14 |      |

##</code><code>##

     | p_1  | p_2  | p_3  | p_4  |
---------------------------------
 v_1 | s_1  | s_2  | s_3  | s_4  |
 v_2 | s_5  | s_6  | s_7  | s_8  |
 v_3 | s_9  | s_10 |
 v_4 | s_11 | s_12 | s_13 |
 v_5 | s_14 |