HDU 4514 (add stack by yourself -- # pragma comment (linker, "/Stack: 102400000,102400000 ″))

The meaning of the question is unknown .. Is it the longest path or a minimal spanning tree?

I only know this data

4 3
1 2 1
1 3 1
1 4 3

4 is obtained by the longest path, and 5 is obtained by the smallest spanning tree... the two are too many...

However, I also learned some things this time, that is, the size of the given stack is very small and there are no 10 ^ 5. So if I want to use DFS to traverse the tree, I need to add the stack space myself.

# Pragma comment (linker, "/Stack: 102400000,102400000") // This is a good thing

The other is better...

 

Longest pathCode

 # Pragma Comment (linker, "/Stack: 102400000,102400000 ") # Include <Stdio. h> # Include < String . H> # Include <Iostream>Using   Namespace  STD;  # Define N 100100 # Define M 10001000 Int  N, m;  Int  Bin [N];  Int  CNT, pre [N];  Int  Mark [N];  Int  MX;  Struct Node {  Int  To, next, W;} edge [m];  Void Add_edge ( Int X, Int Y, Int  W) {edge [CNT]. = Y; edge [CNT]. W = W; edge [CNT]. Next = Pre [X]; Pre [x] = CNT ++ ;}  Int Find ( Int X ){  Int S = X;  While (Bin [s]! = S) S = Bin [s];  While (Bin [x]! = S ){  Int TMP = Bin [X]; bin [x] = S; x = TMP ;}  Return  S ;}  Int DFS (Int  S ){  Int FI = 0 , Se = 0  ; Mark [s] = 1  ;  For ( Int P = pre [s]; P! =- 1 ; P = Edge [p]. Next ){  Int V = Edge [p].;  If (MARK [v] = 0  ){  Int TMP = DFS (v) + Edge [p]. W;  If (TMP> FI) {fi = TMP ;}  Else  {  If (TMP> Se) Se = TMP ;}}}  If (FI + Se> MX) MX = Fi +Se;  Return  FI ;}  Int  Main (){  While (Scanf ( "  % D  " , & N, & M )! = EOF) {CNT = 0  ; MX =- 1  ; Memset (PRE, - 1 ,Sizeof  (Pre); memset (mark,  0 , Sizeof  (Mark ));  For ( Int I = 0 ; I <n; I ++ ) Bin [I] = I;  Int Flag = 0  ;  For (Int I = 0 ; I <m; I ++ ){  Int  X, Y, key; scanf (  "  % D  " , & X, & Y ,& Key );  Int A = 0 , B = 1  ; = Find (x); B =Find (y); bin [A] = B;  If (A = B) {flag = 1  ;} Add_edge (X, Y, key); add_edge (Y, X, key );}  If (Flag = 1  ) {Printf (  "  Yes \ n  "  ); Continue  ;}  For ( Int I = 1 ; I <= N; I ++ ){  If (MARK [I] = 0  ){  Int  TMP; TMP = DFS (I) ;}} printf (  "  % D \ n "  , MX );}  Return   0  ;}