Online JudgeProblem SetAuthorsOnline ContestsUser
Web Board
Home Page
F.A.Qs
Statistical Charts
Problems
Submit Problem
Online Status
Prob.ID:
Register
Update your info
Authors ranklist
Current Contest
Past Contests
Scheduled Contests
Award Contest
 User ID: Password:
Register

## 水过。。。贴个代码。。

Posted by 597100700 at 2011-09-03 22:29:57 on Problem 2457
```var a,b,c,d,e,m,n,sum,l,r:longint;
list,next,toit:array[0..1000000]of longint;
q,uu,vv,ans:array[0..1000000]of longint;
flag:array[0..50000]of boolean;
procedure make(i,j:longint);
begin
inc(sum);
toit[sum]:=j;
next[sum]:=list[i];
list[i]:=sum;
end;
begin
readln(n,m);
sum:=0;
for a:=1 to n do
begin
readln(c,d);
make(c,d);
end;
l:=0;r:=1;
q[r]:=1;
flag[1]:=true;
while l<r do
begin
inc(l);
e:=q[l];
c:=list[e];
while c>0 do
begin
if not flag[toit[c]] then
begin
flag[toit[c]]:=true;
inc(r);
q[r]:=toit[c];
uu[toit[c]]:=l;
end;
c:=next[c];
end;
end;
if uu[m]=0 then
begin
writeln(-1);
exit;
end;
ans[0]:=0;
while uu[m]<>0 do
begin
inc(ans[0]);
ans[ans[0]]:=m;
m:=q[uu[m]];
end;
writeln(ans[0]+1);
writeln(1);
for a:=ans[0] downto 1 do
writeln(ans[a]);
end.```

Followed by:

Post your reply here:
User ID:
Password:
Title:

Content:

All Rights Reserved 2003-2013 Ying Fuchen,Xu Pengcheng,Xie Di
Any problem, Please Contact Administrator