＿＿＿＿＿＿＿＿＿
|                  |＼
|                  |  ＼
|     ＿＿＿＿     |    |
|    |＼      |    |    |
|    |  ＼＿＿|    |    |
|    |   |    |    |    |
|    |   |    |    |    |
|    |   |    |    |    |
|    |   |    |    |    |
|    |   |    |    |    |
|    |   |    |    |    |
|    |   |    |    |    |
|＿＿|   |＿＿|    |＿＿|