Hangzhou Invitation Pre-day

　　有点惊险的一天。

　　早上11点去杭州的飞机，我和队友们本来计划9点从五山出发的，结果拖迟了十几分钟。幸运的是，地铁速度够快，压哨2分钟从取票处拿到机票了。

　　飞机飞了两个钟就到杭州，然后我们坐机场大巴到武林门，再转的士到酒店。自费的比赛，开支各种心疼。TAT

　　到了酒店，我们入住一间3人房，设备足够简陋，居然还要一人100块一个晚上，继续心疼。TAT

　　然后，查了一下地图，酒店是多么的偏僻。_(:з」∠)_本来以为是在浙工大附近住的，然后我们就可以自助去西湖游一下，最后看到这么偏僻的地方，出去市中心打的要50块，坐公交6点多就收车了，最后就只好决定在酒店呆3天算了。

　　晚餐没有自助餐，不过还是挺丰富的，除了一人一份菜，白饭任拿，饭还送到酒店房间来，勉强没那么多怨言了。

　然后剩下几个钟，就一直卡一道LOJ的几何题1313，以为早上想到的思路应该没错了，结果敲出来还是各种WA。

  1 #include <cstdio>
  2 #include <algorithm>
  3 #include <iostream>
  4 #include <cstring>
  5 
  6 using namespace std;
  7 
  8 struct Point {
  9     int x, y;
 10     Point() {}
 11     Point(int x, int y) : x(x), y(y) {}
 12 } ;
 13 Point operator + (Point a, Point b) { return Point(a.x + b.x, a.y + b.y);}
 14 Point operator - (Point a, Point b) { return Point(a.x - b.x, a.y - b.y);}
 15 bool operator < (Point a, Point b) { return a.x < b.x || a.x == b.x < a.y < b.y;}
 16 inline int crossDet(Point a, Point b) { return a.x * b.y - a.y * b.x;}
 17 inline int crossDet(Point o, Point a, Point b) { return crossDet(a - o, b - o);}
 18 inline int dotDet(Point a, Point b) { return a.x * b.x + a.y * b.y;}
 19 
 20 inline bool onSeg(Point p, Point a, Point b) { return crossDet(p, a, b) == 0 && dotDet(a - p, b - p) < 0;}
 21 
 22 int ptInPoly(Point p, Point *poly, int sz) {
 23     int wn = 0;
 24     poly[sz] = poly[0];
 25     for (int i = 0; i < sz; i++) {
 26         if (onSeg(p, poly[i], poly[i + 1])) return -1;
 27         int k = crossDet(poly[i], poly[i + 1], p);
 28         int d1 = poly[i].y - p.y;
 29         int d2 = poly[i + 1].y - p.y;
 30         if (k > 0 && d1 <= 0 && d2 > 0) wn++;
 31         if (k < 0 && d2 <= 0 && d1 > 0) wn--;
 32     }
 33     if (wn != 0) return 1;
 34     return 0;
 35 }
 36 
 37 int andrew(Point *pt, int n, Point *ch) {
 38     int m = 0;
 39     sort(pt, pt + n);
 40     for (int i = 0; i < n; i++) {
 41         while (m > 1 && crossDet(ch[m - 2], ch[m - 1], pt[i]) <= 0) m--;
 42         ch[m++] = pt[i];
 43     }
 44     int k = m;
 45     for (int i = n - 2; i >= 0; i--) {
 46         while (m > k && crossDet(ch[m - 2], ch[m - 1], pt[i]) <= 0) m--;
 47         ch[m++] = pt[i];
 48     }
 49     if (n > 1) m--;
 50     return m;
 51 }
 52 
 53 const int N = 111;
 54 
 55 int inPoly(Point *mines, int m, Point *poly, int p) {
 56     int ret = 0;
 57     for (int i = 0; i < m; i++) {
 58         if (int t = ptInPoly(mines[i], poly, p)) {
 59             if (t == -1) {
 60                 puts("shit!!!");
 61                 while (1) ;
 62             }
 63             mines[ret++] = mines[i];
 64         }
 65     }
 66     return ret;
 67 }
 68 
 69 bool mat[N][N], res[N][N], cur[N][N];
 70 
 71 bool allOnLeft(Point a, Point b, Point *s, int m) {
 72     for (int i = 0; i < m; i++) {
 73         if (crossDet(a, b, s[i]) >= 0) return false;
 74     }
 75     return true;
 76 }
 77 
 78 int work(Point *holes, int h, Point *mines, int m) {
 79     memset(mat, 0, sizeof(mat));
 80     memset(res, 0, sizeof(res));
 81     for (int i = 0; i < h; i++) {
 82         for (int j = 0; j < h; j++) {
 83             if (i == j) continue;
 84             if (allOnLeft(holes[i], holes[j], mines, m)) mat[i][j] = res[i][j] = true;
 85         }
 86     }
 87 //    for (int i = 0; i < h; i++) {
 88 //        cout << "holes " << holes[i].x << ' ' << holes[i].y << endl;
 89 //    }
 90 //    for (int i = 0; i < m; i++) {
 91 //        cout << "mines " << mines[i].x << ' ' << mines[i].y << endl;
 92 //    }
 93 //    for (int i = 0; i < h; i++) {
 94 //        for (int j = 0; j < h; j++) {
 95 //            cout << mat[i][j];
 96 //        }
 97 //        cout << endl;
 98 //    }
 99 //    cout << "check" << endl;
100     for (int t = 1; t <= h; t++) {
101         for (int i = 0; i < h; i++) {
102             if (res[i][i]) {
103 //                cout << i << endl;
104                 return t;
105             }
106             for (int j = 0; j < h; j++) {
107                 cur[i][j] = res[i][j];
108             }
109         }
110         memset(res, 0, sizeof(res));
111         for (int i = 0; i < h; i++) {
112             for (int k = 0; k < h; k++) {
113                 if (cur[i][k]) {
114                     for (int j = 0; j < h; j++) {
115                         res[i][j] = cur[i][k] && mat[k][j];
116                     }
117                 }
118             }
119         }
120     }
121     puts("damn!");
122     while (1) ;
123     return 0;
124 }
125 
126 int main() {
127     freopen("in", "r", stdin);
128     int T, n, m, g, p;
129     Point holes[N], mines[N], poly[N];
130     cin >> T;
131     for (int cas = 1; cas <= T; cas++) {
132         cin >> n >> m >> g >> p;
133         for (int i = 0; i < n; i++) cin >> holes[i].x >> holes[i].y;
134         for (int i = 0; i < m; i++) cin >> mines[i].x >> mines[i].y;
135         int t = andrew(holes, n, poly);
136 //        cout << "Convex Hull" << endl;
137         int k = inPoly(mines, m, poly, t);
138 //        cout << "inPoly" << endl;
139         int ans1 = (m - k) * g;
140         t = k ? work(holes, n, mines, k) : 0;
141         int ans2 = t * p;
142 //        cout << ans1 << ' ' << ans2 << endl;
143         cout << "Case " << cas << ": " << ans1 + ans2 << endl;
144     }
145     return 0;
146 }

LOJ 1313

　　好不爽的一个晚上。。

　　明天热身，求后天可以爆状态。

——written by Lyon

posted @ 2013-06-01 00:44 LyonLys 阅读(202) 评论(0) 编辑收藏举报

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