找来poj计算几何的题目，做一段时间。

poj
1031 Fence
//1039 Pipe
////1066
1092 Farmland
////1106 Transmitters
////1113 Wall
////1118 Lining Up
1133 Stars
1151 Atlantis
1225 STRICTLY INSCRIBED SIMILAR TRIANGLES
1259 The Picnic
1263 Reflections
// 1264 凸包+判断点是否在多边形内+多边形面积
//1265 Area
1266 Cover an Arc.
////1269 Intersecting Lines
//1271 Nice Milk 半平面交
////1279 Art Gallery
////1288
1294 Not Too Convex Hull
1319 Pipe Fitters
////1329
1347 Triangle
1361 JaWs
////1375 Intervals
//1379 Run Away
////1380
////1385
//1389 Area of Simple Polygons
1408 Fishnet
//1410 Intersection 线段和矩形相交，注意题意
//1418 Viva Confetti 求圆和圆相交的交点，然后计算交点在某个圆内，按极角排序在同一个圆周上的点（记得去重），然后计算每小段弧的中点，然后看这个中点在几个圆盘里，记录这个点和对应的id（可以记成一个点一个id）。最后扫一遍中点，未被遮住的就算到答案里。
另外需要特殊处理的就是，如果一个盘盘未被覆盖，就是它是完整的，或者它完全被覆盖，这样的话计算交点是算不出来的，需要特判。
1428 Hermes’ Colony
1434 Fill the Cisterns!
1444 Parallelepiped walk
////1468
1471 Triangles
////1473 There’s Treasure Everywhere!
////1474
1494 Sunrise
1499 Supercomputer Selection, The Sequel
1500 Polygonal Puzzle
1514 Metal Cutting
1518 Problem Bee
1536 Trains
//1556 The Doors
////1569 Myacm Triangles
1584 A Round Peg in a Ground Hole
1586 Three Sides Make a Triangle
1605 Horse Shoe Scoring
1610 Quad Trees
1623 Squadtrees
1624 This Takes the Cake
1645 BSP Trees
////1654 Area
1660 Princess FroG
1673 EXOCENTER OF A TRIANGLE
1685 Color Tunnels
1687 Buggy Sat
1688 Dolphin Pool
1693 Counting Rectangles
1696 Space Ant
1727 Advanced Causal Measurements (ACM)
1758 Frontier
1765 November Rain
1774 Fold Paper Strips
////1788
1803 Box Art
1810 Covering
1813 Overlapped Shapes
1819 Disks
1834 线段处理
1843 Shire
1851 Map
1871 Bullet Hole
1873 The Fortified Forest
1875 Robot
1877 Flooded!
1881 Sail Race
1899 Farmer Bill’s Problem
1902 Illumination
////1905
1912 A highway and the seven dwarfs
1921 Paper Cut
1927 Area in Triangle
1931 Biometrics
1937 Balanced Food
////1939 Diplomatic License
////1940 Polygon Programming with Ease
1956 Pumps and Pipes
1971 Parallelogram Counting
////1981 Circle and Points
1982 Water Tank
////2002 
////2007 Scrambled Polygon
2012 Triangle Cuts
2016 Ink Blots
2026 As the Crow Flies
2031 Building a Space Station
2036 I Conduit!
2043 Area of Polygons
2048 Monster Trap
2053 Square
2066 Minimax Triangulation
2069 Super Star 最小覆盖球
2074 Line of Sight
////2079 Triangle
2087 Petanque
2098 Ellipse
2130 Jogging
2149 Inherit the Spheres
2150 Crossing Prisms
2164 Find the Border
2165 Gunman
2172 Bricks
2177 Ghost Busters
////2187
2284 That Nice Euler Circuit
////2318
//2354 大地坐标系求球面距离
////2398
///2504 同zoj1892
//2546 求两圆相交面积
////2606
////2610
2621 Parallelepiped
2622 Convex hull
//2653
2686 Traveling by Stagecoach
2687 Earth Observation with a Mobile Robot Team
2747 Shy Polygons
////2780
2839 Convex Hull and Triangle
2932 Coneology
2954 Triangle
3011 Secrets in Shadows
3129 How I Wonder What You Are!
//3130 How I Mathematician Wonder What You Are! 判断是否有核，半平面交
3135 Polygons on the Grid
3334 Connected Gheeves
//3335 Rotating Scoreboard 判断是否有核，半平面交
3347 Kadj Squares
////3348
//3384 Feng Shui 半平面交
3407 Brookebond s’en va en guerre…
3410 Split convex polygon
//3058 求圆与环的相交面积
3597
//3608 Bridge Across Islands 求俩凸包最小距离，