perl circle plot

|                                                                      |
|                     41  40   39   38  37   36   35  34                       |
|                 42                                33                   |
|              43                                      32                |
|            44                                          31              |
|         45                                                30           |
|       46                                                    29         |
|      47                                                      28        |
|    48                                                          27      |
|    49                                                          26      |
|    50                                                                 |
|                                                               25      |
|    1                                                          24      |
|    2                                                          23      |
|      3                                                      22        |
|       4                                                    21         |
|         5                                                20           |
|            6                                          19              |
|              7                                      18                |
|                 8                                17                   |
|                     9  10   11   12  13   14   15  16                       |