POJ1275/ZOJ1420/HDU1529 Cashier Employment (差分约束)

  1 #include <iostream>
  2 #include <cstring>
  3 #include <cstdio>
  4 #include <queue>
  5 #define REP(A,X) for(int A=0;A<X;A++)
  6 using namespace std;
  7 #define INF 0x7fffffff
  8 #define MAXN 10010
  9 struct node{
 10     int v,d,next;
 11 }edge[MAXN];
 12 int head[110];
 13 int inihead[110];
 14 int e=0;
 15 void init()
 16 {
 17     e=0;
 18     REP(i,110)head[i]=-1;
 19 }
 20 void add_edge(int u,int v,int d)
 21 {
 22     edge[e].v=v;
 23     edge[e].d=d;
 24     edge[e].next=head[u];
 25     head[u]=e;
 26     e++;
 27 }
 28 int dis[MAXN];
 29 int vis[MAXN];
 30 int cnt[MAXN];
 31 int r[MAXN];
 32 int num[MAXN];
 33 int spfa(int mid){
 34     REP(i,25)vis[i]=0;
 35     REP(i,25)dis[i]=-INF;
 36     REP(i,25)cnt[i]=0;
 37     queue<int>q;
 38     q.push(0);
 39     vis[0]=1;
 40     cnt[0]++;
 41     dis[0]=0;
 42     while(!q.empty())
 43     {
 44         int x=q.front();
 45         q.pop();
 46         for(int i=head[x];i!=-1;i=edge[i].next)
 47         {
 48             int y=edge[i].v;
 49             int d=edge[i].d;
 50             if(dis[y]<dis[x]+d)
 51             {
 52                 dis[y]=dis[x]+d;
 53                 if(!vis[y])
 54                 {
 55                     q.push(y);
 56                     vis[y]=1;
 57                     cnt[y]++;
 58                     if(cnt[y]>25)return false;
 59                 }
 60             }
 61         }
 62         vis[x]=0;
 63     }
 64     return 1;
 65 
 66 }
 67 
 68 int main()
 69 {
 70     ios::sync_with_stdio(false);
 71     //freopen("in.in","r",stdin);
 72     int t;
 73     scanf("%d",&t);
 74     while(t--)
 75     {
 76         REP(i,24)scanf("%d",&r[i+1]);
 77         int n;
 78         int a;
 79         scanf("%d",&n);
 80         REP(i,25)num[i+1]=0;
 81         REP(i,n){
 82             scanf("%d",&a);
 83             num[a+1]++;
 84         }
 85         init();
 86         for(int i=1;i<=24;i++){
 87             if(i>7)add_edge(i-8,i,r[i]);
 88             add_edge(i,i-1,-num[i]);
 89             add_edge(i-1,i,0);
 90         }
 91         int tempe=e;
 92         REP(i,25)inihead[i]=head[i];
 93         int x=0,y=n;
 94         int ans=INF;
 95         while(x<y)
 96         {
 97             e=tempe;
 98             int mid=(x+y)/2;
 99             REP(i,25) head[i]=inihead[i];
100             for(int i=1;i<8;i++) add_edge(i+16,i,r[i]-mid);
101             add_edge(0,24,mid);
102             if(spfa(mid)){
103                 y=mid;
104                 ans=min(mid,ans);
105             }
106             else{
107                 x=mid+1;
108             }
109         }
110         if(ans>n)printf("No Solution\n");
111         else printf("%d\n",ans);
112     }
113     return 0;
114 }