SZOJ 167 Lca裸题

#include<iostream>
#include<cstdlib>
#include<cstdio>
#include<algorithm>
#include<stack>
#include<cstring>
using namespace std;
stack<int> s;
int g[600001],dep[600001],n,cnt,T,q,sum2[600001];
long long sum1[600001];
int f[600001][21],g1[600001][21];
int root1;
struct node{
    int nxt,to,w,fr;
}e[600001];
inline void addedge(int x,int y,int z){
    e[++cnt].nxt=g[x];g[x]=cnt;e[cnt].to=y;e[cnt].w=z;e[cnt].fr=x;
}
inline void dfs(int u){
    dep[u]=1;s.push(u);
    while(!s.empty()){
        u=s.top();s.pop();
       for(int i=1;i<=19;i++)
               f[u][i]=f[f[u][i-1]][i-1];
        for(int i=1;i<=19;i++)
            g1[u][i]=max(g1[u][i],max(g1[f[u][i-1]][i-1],g1[u][i-1]));
        for(int i=g[u];i;i=e[i].nxt){
            if(!dep[e[i].to]){
                dep[e[i].to]=dep[u]+1;
                f[e[i].to][0]=u;
                g1[e[i].to][0]=e[i].w;
                s.push(e[i].to);
            }
        }
    }
}
inline int swim(int x,int h){
    for(int i=0;h;i++,h>>=1)
        if(h&1) x=f[x][i];
    return x;
}
inline int swim1(int x,int h){
    int maxnum=-100007;
    for(int i=0;h;i++,h>>=1)
        if(h&1){
            maxnum=max(maxnum,g1[x][i]);
            x=f[x][i];
//            printf("g1=%d maxnum=%d\n",g1[x][i],maxnum);
        }
//    printf("mmmax==%d\n",maxnum);
    return maxnum;
}
inline int Lca(int x,int y){
    if(dep[x]<dep[y]){
        int t;
        t=x;
        x=y;
        y=t;
    }
    x=swim(x,dep[x]-dep[y]);
    if(x==y) return x;
    for(int i=19;~i;i--){if(f[x][i]!=f[y][i])x=f[x][i],y=f[y][i];}
    return f[x][0];
}
inline int Lca1(int x,int y){
    if(dep[x]<dep[y]){
        int t;
        t=x;
        x=y;
        y=t;
    }
    int maxnum=swim1(x,dep[x]-dep[y]);
//    printf("swim1 maxnum=%d %d %d\n",maxnum,x,dep[x]-dep[y]);
    x=swim(x,dep[x]-dep[y]);
    if(x==y) return maxnum;
    for(int i=19;~i;i--){
        if(f[x][i]!=f[y][i]){
            maxnum=max(maxnum,max(g1[x][i],g1[y][i]));
            x=f[x][i],y=f[y][i];
        }
    }
    maxnum=max(maxnum,max(g1[x][0],g1[y][0]));
    return maxnum;
}
inline void dfs1(int u){
    s.push(u);
    while(!s.empty()){
        u=s.top();s.pop();
        for(int i=g[u];i;i=e[i].nxt){
            if(e[i].to==f[u][0])continue;
            s.push(e[i].to);
            sum1[e[i].to]=sum1[u]+e[i].w;
            sum2[e[i].to]=sum2[u]^e[i].w;
        }
    }
}
inline void Jimmy(){
    scanf("%d%d",&n,&q);
    for(int i=1,u,v,w;i<=n-1;i++){
        scanf("%d%d%d",&u,&v,&w);
        addedge(u,v,w);addedge(v,u,w);
    }

    //f[1][0]=1;
    dfs(1);
    //for(int i=1;i<=n;i++)cout<<f[i][0]<<",";
    dfs1(1);
    //cout<<sum2[5]<<","<<sum2[1]<<endl;
   for(int i=1,u1,v1,ty;i<=q;i++){
        scanf("%d%d%d",&ty,&u1,&v1);
        if(ty==1) printf("%d\n",sum2[u1]^sum2[v1]);
        if(ty==2) printf("%lld\n",sum1[u1]+sum1[v1]-2*sum1[Lca(u1,v1)]);
        if(ty==3) printf("%d\n",Lca1(u1,v1));
    }
//    printf("FFFFFFFFF    %d %d\n",g1[3][0],g1[3][1]);
    return;
}
int main(){
        Jimmy();
    return 0;
}