HDU 4253 Two Famous Companies

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 #include <algorithm>
 6 #include <climits>
 7 #include <vector>
 8 #include <queue>
 9 #include <cstdlib>
10 #include <string>
11 #include <set>
12 #include <stack>
13 #define LL long long
14 #define pii pair<int,int>
15 #define INF 0x3f3f3f3f
16 using namespace std;
17 const int maxn = 100010;
18 struct arc{
19     int u,v,w,id;
20     arc(int uu = 0,int vv = 0,int ww = 0,int iid = 0){
21         u = uu;
22         v = vv;
23         w = ww;
24         id = iid;
25     }
26     bool operator<(const arc &tmp) const{
27         return w < tmp.w;
28     }
29 };
30 arc e[2][maxn];
31 int uf[maxn],n,m,k,tot1,tot2,cost;
32 int Find(int x){
33     if(x == uf[x]) return x;
34     return uf[x] = Find(uf[x]);
35 }
36 bool uset(int u,int v){
37     int tx = Find(u);
38     int ty = Find(v);
39     if(tx != ty) uf[tx] = ty;
40     return tx != ty;
41 }
42 bool check(int delta){
43     int i,j,cnt;
44     for(i = 0; i <= n; ++i) uf[i] = i;
45     i = j = cnt = cost = 0;
46     arc tmp;
47     while(i < tot1 || j < tot2){
48         if(e[0][i].w + delta <= e[1][j].w){
49             tmp = e[0][i++];
50             tmp.w += delta;
51         }else tmp = e[1][j++];
52         if(uset(tmp.u,tmp.v)){
53             cost += tmp.w;
54             if(!tmp.id) cnt++;
55         }
56     }
57     return cnt >= k;
58 }
59 int main() {
60     int u,v,w,id,cs = 1;
61     while(~scanf("%d %d %d",&n,&m,&k)){
62         for(int i = tot1 = tot2 = 0; i < m; ++i){
63             scanf("%d %d %d %d",&u,&v,&w,&id);
64             if(id) e[1][tot2++] = arc(u,v,w,id);
65             else e[0][tot1++] = arc(u,v,w,id);
66         }
67         e[0][tot1].w = e[1][tot2].w = INF;
68         sort(e[0],e[0]+tot1);
69         sort(e[1],e[1]+tot2);
70         int low = -100,high = 100,mid,delta;
71         while(low <= high){
72             mid = (low + high)>>1;
73             if(check(mid)){
74                 delta = mid;
75                 low = mid + 1;
76             }else high = mid - 1;
77         }
78         check(delta);
79         printf("Case %d: %d\n",cs++,cost - delta*k);
80     }
81     return 0;
82 }