hdu 6393 Traffic Network in Numazu （树链剖分+线段树 ??基环树）

#include<bits/stdc++.h>using namespace std;#define lson l,m,rt<<1#define rson m+1,r,rt<<1|1#define ll long long#define mid int m = (l + r) >> 1const int M = 1e5+10;int cnt,cnt1,head[M],fa[M],dep[M],son[M],siz[M],top[M],tid[M],n,q,vis[M];ll val[M];ll sum[M<<2];struct node{ ???int to,next; ???ll val;}e[M];struct node1{ ???int u,v; ???ll val;}a[M];void add(int u,int v){ ???e[++cnt].to = v;e[cnt].next = head[u];head[u] = cnt;}void dfs1(int u,int faz,int deep){ ???dep[u] = deep; ???fa[u] = faz; ???siz[u] = 1; ???for(int i = head[u];i;i=e[i].next){ ???????int v = e[i].to; ???????if(v == fa[u]) continue; ???????dfs1(v,u,deep+1); ???????siz[u] += siz[v]; ???????if(siz[v] > siz[son[u]]||son[u]==-1) ???????????son[u] = v; ???}}void dfs2(int u,int t){ ???top[u] = t; ???tid[u] = ++cnt1; ???if(son[u] == -1) return ; ???dfs2(son[u],t); ???for(int i = head[u];i;i=e[i].next){ ???????int v = e[i].to; ???????if(v != fa[u]&&v != son[u]) ???????????dfs2(v,v); ???}}void pushup(int rt){ ???sum[rt] = sum[rt<<1] + sum[rt<<1|1];}void build(int l,int r,int rt){ ????if(l == r){ ???????sum[rt] = val[l]; ???????return ; ????} ????mid; ????build(lson); build(rson); ????pushup(rt);}void update(int p,ll c,int l,int r,int rt){ ???if(l == r){ ???????sum[rt] = c; ???????return ; ???} ???mid; ???if(p <= m) update(p,c,lson); ???else update(p,c,rson); ???pushup(rt);}ll query(int L,int R,int l,int r,int rt){ ???if(L <= l&&R >= r) ?return sum[rt]; ???mid; ???ll ret = 0; ???if(L <= m) ret += query(L,R,lson); ???if(R > m) ret += query(L,R,rson); ???return ret;}/*void ct(int l,int r,int rt){ ???if(l == r){ ???????cout<<sum[rt]<<" "; ???????return ; ???} ???mid; ???ct(lson); ct(rson);}*/ll solve(int x,int y){ ???int fx = top[x],fy = top[y]; ???ll ans = 0; ???while(fx != fy){ ???????if(dep[fx] < dep[fy]) swap(fx,fy),swap(x,y); ???????if(fx == 1) ans += query(tid[fx]+1,tid[x],1,n+1,1); ???????else ans += query(tid[fx],tid[x],1,n+1,1); ??????// cout<<x<<" "<<fx<<" "<<ans<<endl; ???????x = fa[fx]; fx = top[x]; ???} ???if(x == y) return ans; ???if(dep[x] > dep[y]) swap(x,y); ???ans += query(tid[son[x]],tid[y],1,n+1,1); ???return ans;}void init(){ ???cnt = cnt1 = 0; ???memset(son,-1,sizeof(son)); ???memset(head,0,sizeof(head)); ???memset(vis,0,sizeof(vis));}int main(){ ???int t; ???scanf("%d",&t); ???while(t--){ ???????scanf("%d%d",&n,&q); ???????init(); ???????int tx,ty = n+1; ???????for(int i = 1;i <= n;i ++){ ???????????scanf("%d%d%lld",&a[i].u,&a[i].v,&a[i].val); ???????????if(vis[a[i].u]&&vis[a[i].v]){ ???????????????tx = a[i].u; ???????????????a[i].u = n+1; ???????????} ???????????vis[a[i].u] = vis[a[i].v] = 1; ???????????add(a[i].u,a[i].v); ???????????add(a[i].v,a[i].u); ???????} ??????// cout<<"jsjd: "<<tx<<" "<<ty<<endl; ???????dfs1(1,0,1); ???????dfs2(1,1); ???????for(int i = 1;i <= n;i ++){ ???????????if(dep[a[i].u] < dep[a[i].v])swap(a[i].u,a[i].v); ???????????val[tid[a[i].u]] = a[i].val; ???????} ???????build(1,n+1,1); ?????// ?ct(1,n+1,1);cout<<endl; ???????while(q--){ ???????????int op,x,y; ???????????scanf("%d%d%d",&op,&x,&y); ???????????if(op == 0) update(tid[a[x].u],y,1,n+1,1); ???????????else{ ???????????????ll num = solve(x,tx)+solve(y,ty); ???????????????ll num1 = solve(x,ty)+solve(y,tx); ???????????????//cout<<"num: "<<num<<"num1 : "<<num1<<"solve "<<solve(x,y)<<endl; ???????????????printf("%lld\n",min(solve(x,y),min(num,num1))); ???????????} ???????} ???} ???return 0;}