HDU 3572 Task Schedule

 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 = 20000;
18 struct arc{
19     int to,flow,next;
20     arc(int x = 0,int y = 0,int z = -1){
21         to = x;
22         flow = y;
23         next = z;
24     }
25 };
26 arc e[maxn*10];
27 int head[maxn],d[maxn],cur[maxn];
28 int tot,S,T,n,m;
29 void add(int u,int v,int flow){
30     e[tot] = arc(v,flow,head[u]);
31     head[u] = tot++;
32     e[tot] = arc(u,0,head[v]);
33     head[v] = tot++;
34 }
35 bool bfs(){
36     memset(d,-1,sizeof(d));
37     queue<int>q;
38     d[T] = 1;
39     q.push(T);
40     while(!q.empty()){
41         int u = q.front();
42         q.pop();
43         for(int i = head[u]; ~i; i = e[i].next){
44             if(e[i^1].flow && d[e[i].to] == -1){
45                 d[e[i].to] = d[u] + 1;
46                 q.push(e[i].to);
47             }
48         }
49     }
50 
51     return d[S] > -1;
52 }
53 int dfs(int u,int low){
54     if(u == T) return low;
55     int tmp = 0,a;
56     for(int &i = cur[u]; ~i; i = e[i].next){
57         if(e[i].flow && d[e[i].to] + 1 == d[u]&&(a=dfs(e[i].to,min(e[i].flow,low)))){
58             e[i].flow -= a;
59             e[i^1].flow += a;
60             tmp += a;
61             low -= a;
62             if(!low) break;
63         }
64     }
65     if(!tmp) d[u] = -1;
66     return tmp;
67 }
68 int dinic(){
69     int ans  = 0;
70     while(bfs()){
71         memcpy(cur,head,sizeof(head));
72         ans += dfs(S,INF);
73     }
74     return ans;
75 }
76 int main() {
77     int cs,pi,si,ei,cao = 1;
78     scanf("%d",&cs);
79     while(cs--){
80         scanf("%d %d",&n,&m);
81         int mx = 0,sum = 0;
82         memset(head,-1,sizeof(head));
83         S = tot = 0;
84         for(int i = 1; i <= n; ++i){
85             scanf("%d %d %d",&pi,&si,&ei);
86             sum += pi;
87             for(int k = si; k <= ei; ++k) add(i,n+k,1);
88             add(S,i,pi);
89             mx = max(mx,ei);
90         }
91         T = n + mx + 1;
92         for(int i = n+1; i < T; ++i) add(i,T,m);
93         printf("Case %d: %s\n\n",cao++,dinic() == sum?"Yes":"No");
94     }
95     return 0;
96 }