hdu4160Dolls【最小路径覆盖】

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <vector>
 5 using namespace std;
 6 
 7 const int maxn = 505;
 8 struct Node {
 9     int x, y, z;
10 }node[maxn];
11 
12 int n;
13 int vis[maxn];
14 int Link[maxn];
15 vector<int> G[maxn];
16 bool Find(int u) {
17     for(int i = 0; i < G[u].size(); i++) {
18         int v = G[u][i];
19         if(!vis[v]) {
20             vis[v] = 1;
21             if(Link[v] == -1 || Find(Link[v])) {
22                 Link[v] = u;
23                 return true;
24             }
25         }
26     }
27     return false;
28 }
29 
30 int solve() {
31     memset(Link, -1, sizeof(Link));
32     int cnt = 0;
33     for(int i = 1; i <= n; i++) {
34         if(G[i].size()) {
35             memset(vis, 0, sizeof(vis));
36             if(Find(i)) cnt++;
37         }
38     }
39     return cnt;
40 }
41 
42 bool check(int i, int j) {
43     if(node[i].x > node[j].x && node[i].y > node[j].y && node[i].z > node[j].z) return true;
44     return false;
45 }
46 
47 int main() {
48     while(scanf("%d",&n) && n) {
49         for(int i = 1; i <= n; i++) {
50             G[i].clear();
51             scanf("%d %d %d",&node[i].x, &node[i].y, &node[i].z);
52         }
53         for(int i = 1; i <= n; i++) {
54             for(int j = 1; j <= n; j++) {
55                 if(i == j) continue;
56                 if(check(i, j)) G[i].push_back(j);
57             }
58         }
59         printf("%d\n", n - solve());
60     }
61     return 0;
62 }