233333想简单了。。。。
题解参见http://hzwer.com/3710.html
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define maxv 4050 #define maxe 200500 #define inf 0x7f7f7f7f7f7f7f7fLL using namespace std; struct edge { long long u,v,w,flag,nxt; }e[maxe]; long long n,m,x,y,a,b,g[maxv],nume=0,dis[maxv]; long long top[maxv],fath[maxv],dfn[maxv],dep[maxv],size[maxv],son[maxv],times=0; long long root,tot=0,ls[maxv<<2],rs[maxv<<2],lazy[maxv<<2]; void addedge(long long u,long long v,long long w,long long flag) { e[++nume].u=u; e[nume].v=v; e[nume].w=w; e[nume].flag=flag; e[nume].nxt=g[u]; g[u]=nume; } void dfs1(long long x) { size[x]=1;son[x]=0; for (long long i=g[x];i;i=e[i].nxt) { long long v=e[i].v; if ((e[i].flag) && (v!=fath[x])) { fath[v]=x;dep[v]=dep[x]+1;dis[v]=dis[x]+e[i].w; dfs1(v); size[x]+=size[v]; if (size[v]>size[son[x]]) son[x]=v; } } } void dfs2(long long x,long long father) { dfn[x]=++times;top[x]=father; if (son[x]) dfs2(son[x],father); for (long long i=g[x];i;i=e[i].nxt) { long long v=e[i].v; if ((e[i].flag) && (v!=fath[x]) && (v!=son[x])) dfs2(v,v); } } void build(long long &now,long long left,long long right) { now=++tot;lazy[now]=inf; if (left==right) return; long long mid=(left+right)>>1; build(ls[now],left,mid); build(rs[now],mid+1,right); } void modify(long long now,long long left,long long right,long long l,long long r,long long x) { if ((left==l) && (right==r)) { lazy[now]=min(lazy[now],x); return; } long long mid=(left+right)>>1; if (r<=mid) modify(ls[now],left,mid,l,r,x); else if (l>=mid+1) modify(rs[now],mid+1,right,l,r,x); else {modify(ls[now],left,mid,l,mid,x);modify(rs[now],mid+1,right,mid+1,r,x);} } long long lca(long long u,long long v) { long long f1=top[u],f2=top[v]; while (f1!=f2) { if (dep[f1]<dep[f2]) {swap(f1,f2);swap(u,v);} u=fath[f1];f1=top[u]; } if (dep[u]<dep[v]) return u; else return v; } void work(long long x) { long long u=e[x].u,v=e[x].v,ret=dis[u]+e[x].w+dis[v]; long long t=lca(u,v); if (t==v) return; u=t; long long f1=top[u],f2=top[v]; while (f1!=f2) { if (dep[f1]<dep[f2]) {swap(f1,f2);swap(u,v);} modify(root,1,n,dfn[f1],dfn[u],ret); u=fath[f1];f1=top[u]; } if (u!=v) { if (dep[u]>dep[v]) swap(u,v); modify(root,1,n,dfn[u]+1,dfn[v],ret); } } long long ask(long long now,long long left,long long right,long long pos) { if (left==right) return lazy[now]; long long mid=(left+right)>>1; if (pos<=mid) return min(ask(ls[now],left,mid,pos),lazy[now]); else return min(ask(rs[now],mid+1,right,pos),lazy[now]); } int main() { scanf("%lld%lld",&n,&m); for (long long i=1;i<=m;i++) { scanf("%lld%lld%lld%lld",&x,&y,&a,&b); addedge(x,y,a,b); addedge(y,x,a,b); } dfs1(1); dfs2(1,1); build(root,1,n); for (long long i=1;i<=nume;i++) { long long u=e[i].u,v=e[i].v,ret=dis[u]+e[i].w+dis[v]; if (e[i].flag) continue; work(i); } for (long long i=2;i<=n;i++) { long long ret=ask(root,1,n,dfn[i]); if (ret==inf) printf("-1 "); else printf("%lld ",ret-dis[i]); } printf("\n"); return 0; }
时间: 2024-10-07 10:52:33