Zju zoj 2588 perform edge double connection of the cut edge Template

Ultimate Template

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# Include <stdio. h>
# Include < String . H>
# Include <algorithm>
 Using   Namespace STD;
 Const   Int N = 10010 ;
 Const   Int M = 100010 ;
Int Min ( Int A, Int B ){
 Return A> B? B:;
}
 Struct Edge {
 Int To, next, ID;
} Edge [ 2 * M];
 Int N, m, TOT, tdfn, nbridge;
 Int Head [N], vis [N], low [N], dfn [N], bridge [m];
 Void Add (Int A, Int B, Int Edgeid ){
 //  This method is slow in determining the duplicate edge.  
      /*  For (j = head [a]; J! =-1; j = edge [J]. Next ){
If (B = edge [J].)
Break;
}
If (J! =-1)
{
Edge [J]. Tag = 1;
Edge [J ^ 1]. Tag = 1;
Return;
}  */ 
Edge [tot]. To = B;
Edge [tot]. ID = edgeid;
Edge [tot]. Next = head [a];
Head [a] = tot ++;
Edge [tot]. To =;
Edge [tot]. ID = edgeid;
Edge [tot]. Next = head [B];
Head [B] = tot ++;
}
 Void DFS ( Int U, Int FA ){
 Int I, V; low [u] = dfn [u] = ++ tdfn; vis [u] = 1 ;
 For (I = head [u]; I! =- 1 ; I = edge [I]. Next ){
V = edge [I].;
 If (Vis [v] = 1 & Edge [I]. ID! = FA) low [u] = min (low [u], dfn [v]);
 Else   If (! Vis [v])
{
DFS (v, edge [I]. ID );
Low [u] = min (low [u], low [v]);
 If (Low [v]> dfn [u]) {
Bridge [edge [I]. ID] = ++ nbridge;
}
}
}
Vis [u] = 2 ;
}
Void Init (){
 Int I;
Tdfn = 1 ; Tot = 0 ; Nbridge = 0 ;
 For (I = 0 ; I <= N; I ++) head [I] =- 1 ;
 For (I = 1 ; I <= m; I ++) Bridge [I] = 0 ;
 For (I = 1 ; I <= N; I ++) vis [I] = 0 ;
}
 Int Main ()
{
 Int I, K, T;
 Int U, V;
Scanf ( "  % D  " , & T );
 While (T --){
Scanf ( "  % D " , & N, & M );
Init ();
 For (K = 1 ; K <= m; k ++)
{
Scanf ( "  % D  " , & U, & V );
Add (u, v, k );
}
DFS ( 1 , 0 );
Printf ( " % D \ n  " , Nbridge );
 For (I = 1 , K = nbridge; I <= m; I ++)
{
 If (Bridge [I])
{
Printf ( "  % D  " , I );
 If (-- K) printf ( "   " );
}
}
 If (Nbridge) printf ( "  \ N  " );
 If (T) printf ( "  \ N  " );
}
 Return   0 ;
}