Codeforces Round #303 (Div. 2) E. Paths and Trees (shortest path + deform minimum spanning tree)

Title Address: E. Paths and Trees
Simulate a CF, this is really too water. To play while doing. The last half-minute has been handed an e question. Unfortunately AK failed in the lore ....
First of all, the idea must first seek the shortest way, may be the most short-circuit side to pick out, and then the second step I originally wrote is directly using the smallest tree of the graph, so the failure of the lore ... Later found that this is not possible. Because the edge is a forward edge, and each point in the degree to ensure that only one line. So I made the edge of the smallest spanning tree into a forward edge, and then judged that the entry for each point was guaranteed to be 1. And then it's over.
The code is as follows:

#include <iostream>#include <string.h>#include <math.h>#include <queue>#include <algorithm>#include <stdlib.h>#include <map>#include <set>#include <stdio.h>#include <time.h>using namespace STD;#define LL __int64#define PI ACOs ( -1.0)#pragma COMMENT (linker, "/stack:1024000000")Const intMod=9901;Const intinf=0x3f3f3f3f;Const Doubleeqs=1e-9;Const intmaxn=300000+Ten;intHEAD[MAXN], CNT, HA[MAXN], VIS[MAXN]; LL D[MAXN];structnode{intU, V, next; LL W;} edge[maxn<<1];voidAddintUintV, LL W) {edge[cnt].v=v;        Edge[cnt].w=w;        Edge[cnt].next=head[u]; head[u]=cnt++;}voidSPFA (intST) { Queue<int>Q Q.push (ST);memset(Vis,0,sizeof(VIS)); d[st]=0; while(!q.empty ()) {intU=q.front ();                Q.pop (); vis[u]=0; for(inti=head[u];i!=-1; i=edge[i].next) {intV=EDGE[I].V;if(D[V]&GT;D[U]+EDGE[I].W) {D[V]=D[U]+EDGE[I].W;if(!vis[v]) {vis[v]=1;                                Q.push (v); }                        }                }        }}structnode1{intU, V, id; LL W;} FEI[MAXN];inttot=0, BIN[MAXN], IN[MAXN];intFind1 (intx) {returnBin[x]==x?x:bin[x]=find1 (Bin[x]);}BOOLCMP (Node1 F1, Node1 F2) {returnF1.W&LT;F2.W;}voidInitintN) { for(intI=1; i<=n;i++) bin[i]=i;memset(In,0,sizeof(in));}voidKrus (intNintm) {sort (fei,fei+tot,cmp);intI LL ans=0; Init (n); for(i=0; i<tot;i++) {intu=fei[i].u;intV=FEI[I].V;if(In[v])Continue;intF1=find1 (bin[fei[i].u]);intF2=find1 (BIN[FEI[I].V]);if(F1!=F2)                        {bin[f2]=f1;                        ANS+=FEI[I].W; ha[fei[i].id]=1;                in[v]++; }        }printf("%i64d\n", ans); for(intI=1; i<=m;i++) {if(Ha[i]) {printf("%d", i); }                }puts("");}intMain () {intN, M, I, J, u, V; LL W, ans; while(scanf("%d%d", &n,&m)!=eof) {memset(head,-1,sizeof(head)); Cnt=0; for(i=1; i<=n;i++) {d[i]= (LL)1e16; } for(i=1; i<=m;i++) {scanf("%d%d%i64d", &u,&v,&w);                        Add (U,V,W);                Add (V,U,W); }scanf("%d", &u); SPFA (U);memset(Ha,0,sizeof(ha)); ans=0; for(i=1; i<=n;i++) { for(j=head[i];j!=-1; j=edge[j].next) {intV =EDGE[J].V;if(D[i]+edge[j].w==d[v])                                        {fei[tot].u=i;                                        Fei[tot].v=v;                                        FEI[TOT].W=EDGE[J].W; fei[tot++].id=j/2+1;        }}} Krus (N,m); }return 0;}

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Codeforces Round #303 (Div. 2) E. Paths and Trees (shortest path + deform minimum spanning tree)