hdu 3572 Task Schedule 网络流

  1 #include<bits/stdc++.h>
  2 using namespace std;
  3 #define pb(x) push_back(x)
  4 #define ll long long
  5 #define mk(x, y) make_pair(x, y)
  6 #define lson l, m, rt<<1
  7 #define mem(a) memset(a, 0, sizeof(a))
  8 #define rson m+1, r, rt<<1|1
  9 #define mem1(a) memset(a, -1, sizeof(a))
 10 #define mem2(a) memset(a, 0x3f, sizeof(a))
 11 #define rep(i, a, n) for(int i = a; i<n; i++)
 12 #define ull unsigned long long
 13 typedef pair<int, int> pll;
 14 const double PI = acos(-1.0);
 15 const double eps = 1e-8;
 16 const int mod = 1e9+7;
 17 const int inf = 1061109567;
 18 const int dir[][2] = { {-1, 0}, {1, 0}, {0, -1}, {0, 1} };
 19 const int maxn = 5e6+5;
 20 int head[maxn*2], s, t, num, q[maxn*2], dis[10000];
 21 struct node
 22 {
 23     int to, nextt, c;
 24 }e[maxn*2];
 25 void init() {
 26     mem1(head);
 27     num = 0;
 28 }
 29 void add(int u, int v, int c) {
 30     e[num].to = v; e[num].nextt = head[u]; e[num].c = c; head[u] = num++;
 31     e[num].to = u; e[num].nextt = head[v]; e[num].c = 0; head[v] = num++;
 32 }
 33 int bfs() {
 34     int u, v, st = 0, ed = 0;
 35     mem(dis);
 36     dis[s] = 1;
 37     q[ed++] = s;
 38     while(st<ed) {
 39         u = q[st++];
 40         for(int i = head[u]; ~i; i = e[i].nextt) {
 41             v = e[i].to;
 42             if(e[i].c&&!dis[v]) {
 43                 dis[v] = dis[u]+1;
 44                 if(v == t)
 45                     return 1;
 46                 q[ed++] = v;
 47             }
 48         }
 49     }
 50     return 0;
 51 }
 52 int dfs(int u, int limit) {
 53     if(u == t)
 54         return limit;
 55     int cost = 0;
 56     for(int i = head[u]; ~i; i = e[i].nextt) {
 57         int v = e[i].to;
 58         if(e[i].c&&dis[u] == dis[v]-1) {
 59             int tmp = dfs(v, min(limit-cost, e[i].c));
 60             if(tmp>0) {
 61                 e[i].c -= tmp;
 62                 e[i^1].c += tmp;
 63                 cost += tmp;
 64                 if(cost == limit)
 65                     break;
 66             } else {
 67                 dis[v] = -1;
 68             }
 69         }
 70     }
 71     return cost;
 72 }
 73 int dinic() {
 74     int ans = 0;
 75     while(bfs()) {
 76         ans += dfs(s, inf);
 77     }
 78     return ans;
 79 }
 80 int main()
 81 {
 82     int T, m, n, x, y, w;
 83     cin>>T;
 84     for(int CASE = 1; CASE<=T; CASE++) {
 85         scanf("%d%d", &n, &m);
 86         init();
 87         int sum = 0, max_day = 0;
 88         s = 0;
 89         for(int i = 1; i<=n; i++) {
 90             scanf("%d%d%d", &w, &x, &y);
 91             add(s, i, w);
 92             for(int j = x; j<=y; j++) {
 93                 add(i, j+n, 1);
 94             }
 95             max_day = max(max_day, y);
 96             sum += w;
 97         }
 98         t = n+max_day+1;
 99         for(int i = n+1; i<=n+max_day; i++)
100             add(i, t, m);
101         int ans = dinic();
102         printf("Case %d: ", CASE);
103         if(ans == sum) {
104             cout<<"Yes"<<endl;
105         } else {
106             cout<<"No"<<endl;
107         }
108         cout<<endl;
109     }
110 }