7 7 0 0
1 10000.  10000. 0.
2 15000.  5000.  0.
3 20000.  5000.  0.
4 20000.  0.     0.
5 0.      0.     0.
6 0.      5000.  0.
7 5000.   5000.  0.
1 1 line 1 2
2 1 line 2 3
3 1 line 3 4
4 1 line 4 5
5 1 line 5 6
6 1 line 6 7
7 1 line 7 1