boost/libs/polygon/example/input_data/primary/primary_035.txt

0
20
100 0 95 30
95 30 80 58
80 58 58 80
58 80 30 95
30 95 0 99
0 99 -30 95
-30 95 -58 80
-58 80 -80 58
-80 58 -95 30
-95 30 -99 0
-99 0 -95 -30
-95 -30 -80 -58
-80 -58 -58 -80
-58 -80 -30 -95
-30 -95 0 -99
0 -99 30 -95
30 -95 58 -80
58 -80 80 -58
80 -58 95 -30
95 -30 100 0