最大流

 1 const maxn=1000; maxe=2000;
 2 type
 3   node=record
 4     f,t,l,re:longint;
 5   end;
 6 var m,n,i,j,u,v,x,f,t,num:longint;
 7 e,h,head:array[0..maxn] of longint;
 8 b:array[0..maxe] of node;
 9 function min(a,b:longint):longint;
10 begin
11   if a>b then exit(b)
12     else exit(a);
13 end;
14 procedure insert(u,v,x,rev:longint);
15 begin
16   inc(num);
17   with b[num] do
18     begin
19       f:=head[u];
20       t:=v;
21       l:=x;
22       re:=rev;
23     end;
24   head[u]:=num;
25 end;
26 function findnode:longint;
27 var i:longint;
28 begin
29   for i:=2 to n-1 do
30     if e[i]>0 then exit(i);
31   exit(0);
32 end;
33 function push(u:longint):boolean;
34 var nowe,flow,v:longint;
35 begin
36   nowe:=head[u]; push:=true;
37   while nowe<>0 do
38     begin
39       v:=b[nowe].t;
40       if (h[v]+1=h[u]) and (b[nowe].l>0) then
41         begin
42           flow:=min(e[u],b[nowe].l);
43           dec(e[u],flow);
44           dec(b[nowe].l,flow);
45           inc(e[v],flow);
46           inc(b[b[nowe].re].l,flow);
47           push:=false;
48         end;
49       nowe:=b[nowe].f;
50     end;
51 end;
52 procedure relable(u:longint);
53 var minh,v,nowe:longint;
54 begin
55   minh:=maxn;
56   nowe:=head[u];
57   while nowe<>0 do
58     begin
59       v:=b[nowe].t;
60       if b[nowe].l>0 then minh:=min(minh,h[v]);
61       nowe:=b[nowe].f;
62     end;
63   h[u]:=minh+1;
64 end;
65 begin
66   readln(m,n); f:=1; t:=n;
67   for i:=1 to m do
68     begin
69       readln(u,v,x);
70       if u=v then continue;
71       insert(u,v,x,num+2);
72       insert(v,u,0,num);
73     end;
74   u:=head[f];
75   while u<>0 do
76     begin
77       v:=b[u].t; x:=b[u].l;
78       inc(e[v],x);
79       dec(e[f],x);
80       b[b[u].re].l:=x;
81       b[u].l:=0;
82       u:=b[u].f;
83     end;
84   h[f]:=n+1;
85   u:=findnode;
86   while u<>0 do
87   begin
88     if push(u) then relable(u);
89     u:=findnode;
90   end;
91   writeln(e[n]);
92 end.

  1 const inf=1000000000; maxe=1000000; maxn=10000;
  2 type
  3   node=record
  4     f,t,c,d:longint;
  5   end;
  6 var n,a,b,fbuy,fa,fb,i,s,t,x,num,ans,temp:longint;
  7 e:array[0..maxe] of node;
  8 head,go,d:array[0..maxn] of longint;
  9 f:array[0..maxe] of longint;
 10 p:array[0..maxn] of boolean;
 11 procedure insert(u,v,x,y:longint);
 12 begin
 13   e[num].f:=head[u];
 14   e[num].t:=v;
 15   e[num].c:=x;
 16   e[num].d:=y;
 17   head[u]:=num;
 18   inc(num);
 19 end;
 20 procedure add(u,v,x,y:longint);
 21 begin
 22   insert(u,v,x,y);
 23   insert(v,u,0,-y);
 24 end;
 25 function spfa:boolean;
 26 var l,r,edge,now,v:longint;
 27 begin
 28   fillchar(p,sizeof(p),true);
 29   fillchar(go,sizeof(go),255);
 30   for l:=1 to t do d[l]:=inf;
 31   l:=1; r:=1; f[1]:=s; d[s]:=0; p[s]:=false; temp:=0;
 32   while l<=r do
 33     begin
 34       now:=f[l];
 35       edge:=head[now];
 36       while edge<>-1 do
 37         begin
 38           v:=e[edge].t;
 39           if (d[v]>d[now]+e[edge].d) and (e[edge].c>0) then
 40             begin
 41               d[v]:=d[now]+e[edge].d;
 42               go[v]:=edge;
 43               if p[v] then
 44                 begin
 45                   p[v]:=false;
 46                   inc(r);
 47                   f[r]:=v;
 48                 end;
 49             end;
 50           edge:=e[edge].f;
 51         end;
 52       inc(l);
 53       p[now]:=true;
 54     end;
 55   if d[t]=inf then exit(false)
 56     else begin
 57       temp:=d[t];
 58       exit(true);
 59     end;
 60 end;
 61 function min(a,b:longint):longint;
 62 begin if a>b then exit(b) else exit(a); end;
 63 function calc:longint;
 64 var now:longint;
 65 begin
 66   now:=t; calc:=inf;
 67   while go[now]<>-1 do
 68     begin
 69       calc:=min(calc,e[go[now]].c);
 70       now:=e[go[now] xor 1].t;
 71     end;
 72   now:=t;
 73   while go[now]<>-1 do
 74     begin
 75       dec(e[go[now]].c,calc);
 76       inc(e[go[now] xor 1].c,calc);
 77       now:=e[go[now] xor 1].t;
 78     end;
 79 end;
 80 begin
 81   readln(n,a,b,fbuy,fa,fb);
 82   fillchar(e,sizeof(e),255);
 83   fillchar(head,sizeof(head),255);
 84   s:=2*n+1; t:=s+1;
 85   for i:=1 to n do
 86     begin
 87       read(x);
 88       if i+1<=n then add(i,i+1,inf,0);
 89       if i+a+1<=n then add(i,n+i+a+1,inf,fa);
 90       if i+b+1<=n then add(i,n+i+b+1,inf,fb);
 91       add(s,n+i,inf,fbuy);
 92       add(s,i,x,0);
 93       add(n+i,t,x,0);
 94     end;
 95   while spfa do
 96     begin
 97       //writeln(temp);
 98       inc(ans,temp*calc);
 99     end;
100   writeln(ans);
101 end.