P3245: 最快路线
这道题其实还是不难的，只是自己搞混了=-=//晕，做了好久啊，其实就是个spfa，关键是存储路径搞昏了。输出格式要求太严了，航模不能有空格啊，所以因为格式WA了三次，哭啊/(ㄒoㄒ)/~~。贴上代码吧=-=。
1 const maxn=100000;
2 type
3 link=^node;
4 node=record
5 t,v,l:longint;
6 f:link;
7 end;
8 var n,m,s,t,v,l,i,j,toto,sp:longint;
9 dis:double;
10 adj:array[0..500] of link;
11 bl:array[0..500,0..500] of boolean;
12 f,speed:array[0..1000000] of longint;
13 go:array[0..500,0..500,1..2] of longint;
14 d:array[0..500,0..500] of double;
15 procedure insert(s,t,v,l:longint);
16 var p:link;
17 begin
18 new(p);
19 p^.f:=adj[s];
20 p^.t:=t;
21 p^.v:=v;
22 p^.l:=l;
23 adj[s]:=p;
24 end;
25 procedure spfa;
26 var p:link;
27 now,l,r,v:longint;
28 begin
29 for l:=0 to 500 do
30 for r:=0 to n do d[l,r]:=maxn;
31 fillchar(bl,sizeof(bl),true);
32 l:=1; r:=1; d[70,1]:=0; f[1]:=1; bl[70,1]:=false; go[70,1,1]:=1; speed[1]:=70;
33 while l<=r do
34 begin
35 now:=f[l];
36 v:=speed[l];
37 p:=adj[now];
38 while p<>nil do
39 begin
40 if p^.v<>0 then
41 begin
42 if d[v,now]+(p^.l/p^.v)<d[p^.v,p^.t] then
43 begin
44 d[p^.v,p^.t]:=d[v,now]+(p^.l/p^.v);
45 go[p^.v,p^.t,1]:=now;
46 go[p^.v,p^.t,2]:=v;
47 if bl[p^.v,p^.t] then
48 begin
49 bl[p^.v,p^.t]:=false;
50 inc(r);
51 f[r]:=p^.t;
52 speed[r]:=p^.v;
53 end;
54 end;
55 end
56 else begin
57 if d[v,now]+(p^.l/v)<d[v,p^.t] then
58 begin
59 d[v,p^.t]:=d[v,now]+(p^.l/v);
60 go[v,p^.t,1]:=now;
61 go[v,p^.t,2]:=v;
62 if bl[v,p^.t] then
63 begin
64 bl[v,p^.t]:=false;
65 inc(r);
66 f[r]:=p^.t;
67 speed[r]:=v;
68 end;
69 end;
70 end;
71 p:=p^.f;
72 end;
73 inc(l);
74 bl[v,now]:=true;
75 end;
76 end;
77 procedure print(x,v:longint);
78 begin
79 if (x<>1) then print(go[v,x,1],go[v,x,2]);
80 if x<>toto then write(x-1,' ')
81 else write(x-1);
82 end;
83 begin
84 readln(n,m,toto);
85 inc(toto);
86 for i:=1 to m do
87 begin
88 readln(s,t,v,l);
89 insert(s+1,t+1,v,l);
90 end;
91 spfa;
92 dis:=maxn;
93 for i:=0 to 500 do
94 if d[i,toto]<dis then
95 begin
96 dis:=d[i,toto];
97 sp:=i;
98 end;
99 print(toto,sp);
100 end.
(转载请注明出处：http://www.cnblogs.com/Kalenda/)
