sicily 1024 Magic Island

题意：求无向图路径中的最大带权值.

解法：深搜

 1 // Problem#: 9859

 2 // Submission#: 2661875

 3 // The source code is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License

 4 // URI: http://creativecommons.org/licenses/by-nc-sa/3.0/

 5 // All Copyright reserved by Informatic Lab of Sun Yat-sen University

 6 #include<iostream>

 7 #include<vector>

 8 #include<stack>

 9 #include<memory.h>

10 using namespace std;

11 

12 struct  Road{

13     int From;

14     int Dest;

15     int Dist;

16     Road(int f,int de,int di){

17         From = f;

18         Dest = de;

19         Dist = di;

20     }

21 };

22 vector<Road> roads[10001];

23 bool visited[10001];

24 

25 int longest;

26 void DSF(int k,int cur){

27     if(cur > longest){

28         longest = cur;

29     }

30     visited[k] = true;

31     for(int i=0;i<roads[k].size();i++){

32         int dest = roads[k][i].Dest;

33         int dist = roads[k][i].Dist;

34         if(visited[dest])

35             continue;

36         DSF(dest,cur+dist);

37     }

38     //clear visited mark

39     visited[k] = false;

40 }

41 int main(){

42     int N,K;

43     while(cin>>N>>K){

44         int from,dest,dist;

45         longest = 0;

46         memset(roads,0,sizeof(roads));

47         memset(visited,false,sizeof(visited));

48         //input 

49         for(int i=0;i<N-1;i++){

50             cin >> from >> dest >> dist;

51             Road rF = Road(from,dest,dist);

52             Road rD = Road(dest,from,dist);

53             roads[from].push_back(rF);

54             roads[dest].push_back(rD);

55         }

56         DSF(K,longest);

57         cout << longest <<endl;

58     }

59     return 0;

60 }