HDU 3072 SCC Intelligence System

Give a weighted graph to connect the whole graph. The points in the SCC are spent 0, so the weight of the minimum edge is reduced by the first point, then the weighted value between the two points after the point is shrunk, and the sum of these weights is the answer.

1#include <iostream>2#include <cstdio>3#include <algorithm>4#include <cstring>5#include <vector>6#include <stack>7 using namespacestd;8 9 intN, M;Ten  One Const intMAXN =50000+Ten; A  -vector<int>G[MAXN], C[MAXN]; -  thestack<int>S; - intPRE[MAXN], LOWLINK[MAXN], SCCNO[MAXN]; - intDfs_clock, scc_cnt; -  + voidDfsintu) - { +Pre[u] = Lowlink[u] = + +Dfs_clock; A s.push (u); at      for(inti =0; I < g[u].size (); i++) -     { -         intv =G[u][i]; -         if(!Pre[v]) -         { - Dfs (v); inLowlink[u] =min (Lowlink[u], lowlink[v]); -         } to         Else if(!sccno[v]) lowlink[u] =min (Lowlink[u], pre[v]); +     } -  the     if(Lowlink[u] = =Pre[u]) *     { $scc_cnt++;Panax Notoginseng          for(;;) -         { the             intx =S.top (); S.pop (); +SCCNO[X] =scc_cnt; A             if(x = = u) Break; the         } +     } - } $  $ voidFIND_SCC () - { -Dfs_clock = scc_cnt =0; thememset (PRE,0,sizeof(pre)); -memset (Sccno,0,sizeof(SCCNO));Wuyi      for(inti =0; I < n; i++)if(!Pre[i]) DFS (i); the } -  Wu intCOST[MAXN]; -  About intMain () $ { -      while(SCANF ("%d%d", &n, &m) = =2) -     { -          for(inti =0; I < n; i++) {g[i].clear (); C[i].clear (); } A          while(m--) +         { the             intU, V, D; scanf"%d%d%d", &u, &v, &d); - G[u].push_back (v); C[u].push_back (d); $         } the FIND_SCC (); the  thememset (Cost,-1,sizeof(cost)); the          for(inti =0; I < n; i++) -              for(intj =0; J < G[i].size (); J + +) in             { the                 intU = sccno[i], V =Sccno[g[i][j]]; the                 if(U = = v)Continue; About                 if(Cost[v] = =-1) Cost[v] =C[i][j]; the                 ElseCOST[V] =min (Cost[v], c[i][j]); the             } the  +         intAns =0; -          for(inti =1; I <= scc_cnt; i++)if(Cost[i]! =-1) ans + =Cost[i]; theprintf"%d\n", ans);Bayi     } the  the     return 0; -}

code June

HDU 3072 SCC Intelligence System