正题

P3401

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题目大意

给你一棵树，让你进行以下操作

1. 修改一条边的边权
2. 查询一条路径的所有子路径异或值的和

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解题思路

记下所有点到根节点的路径亦或值，那么查询就是所有点对的异或值之和

因为边权<1024，最多只有10位，所以可以树链剖分，然后统计每一位1的数量，最后乘起来

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code

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#define ll long long
#define N 30010
using namespace std;
ll n,q,x,y,z,w,sum,num,tot,v[N],vv[N],h[N],hs[N],fa[N],sz[N],dep[N],low[N],dfn[N],top[N];
struct rec
{ll to,nx,l;
}e[N<<1];
struct node
{ll a[10];node operator +(const node &b){node c;for(ll i=0;i<10;++i)c.a[i]=a[i]+b.a[i];return c;}
};
struct Tree
{#define ls x*2#define rs x*2+1node s[N<<2];int lazy[N<<2];void push_up(ll x){s[x]=s[ls]+s[rs];return;}void get(ll x,ll l,ll r,ll y){lazy[x]^=y;for(int i=0;i<10;++i)if(y&(1<<i))s[x].a[i]=r-l+1-s[x].a[i];return;}void push_down(ll x,ll l,ll r){if(lazy[x]){int mid=l+r>>1;get(ls,l,mid,lazy[x]);get(rs,mid+1,r,lazy[x]);lazy[x]=0;}return;}void change(ll x,ll l,ll r,ll y,ll z){if(l==r){for(ll i=0;i<10;++i)s[x].a[i]=z&1,z>>=1;return;}ll mid=l+r>>1;if(y<=mid)change(ls,l,mid,y,z);else change(rs,mid+1,r,y,z);push_up(x);return;}void chg(ll x,ll L,ll R,ll l,ll r,ll z){if(L==l&&R==r){get(x,L,R,z);return;}ll mid=L+R>>1;push_down(x,L,R);if(r<=mid)chg(ls,L,mid,l,r,z);else if(l>mid)chg(rs,mid+1,R,l,r,z);else chg(ls,L,mid,l,mid,z),chg(rs,mid+1,R,mid+1,r,z);push_up(x);return;}node ask(ll x,ll L,ll R,ll l,ll r){if(L==l&&R==r)return s[x];ll mid=L+R>>1;push_down(x,L,R);if(r<=mid)return ask(ls,L,mid,l,r);else if(l>mid)return ask(rs,mid+1,R,l,r);else return ask(ls,L,mid,l,mid)+ask(rs,mid+1,R,mid+1,r);}
}T;
void add(ll x,ll y,ll z)
{e[++tot].to=y;e[tot].l=z;e[tot].nx=h[x];h[x]=tot;return;
}
void dfs1(ll x)
{sz[x]=1;for(ll i=h[x];i;i=e[i].nx){ll y=e[i].to;if(y==fa[x])continue;dep[y]=dep[x]+1;v[y]=v[x]^e[i].l;vv[y]=e[i].l;fa[y]=x;dfs1(y);sz[x]+=sz[y];if(sz[y]>sz[hs[x]])hs[x]=y;}return;
}
void dfs2(ll x,ll anc)
{top[x]=anc;dfn[x]=++w;T.change(1,1,n,dfn[x],v[x]);if(hs[x])dfs2(hs[x],anc);for(ll i=h[x];i;i=e[i].nx){ll y=e[i].to;if(y==fa[x]||y==hs[x])continue;dfs2(y,y);}low[x]=w;return;
}
node ask(ll x,ll y)
{node now;for(ll i=0;i<10;++i)now.a[i]=0;while(top[x]!=top[y]){if(dep[top[x]]<dep[top[y]])swap(x,y);now=now+T.ask(1,1,n,dfn[top[x]],dfn[x]);x=fa[top[x]];}if(dep[x]>dep[y])swap(x,y);now=now+T.ask(1,1,n,dfn[x],dfn[y]);z=x;return now;
}
int main()
{scanf("%lld%lld",&n,&q);for(ll i=1;i<n;++i){scanf("%lld%lld%lld",&x,&y,&z);add(x,y,z);add(y,x,z);}dep[1]=1;fa[1]=1;dfs1(1);dfs2(1,1);while(q--){scanf("%lld",&x);if(x&1){scanf("%lld%lld",&x,&y);node g=ask(x,y);sum=0;num=dep[x]-dep[z]+dep[y]-dep[z]+1;for(ll i=0;i<10;++i)sum+=(1<<i)*(num-g.a[i])*g.a[i];printf("%lld\n",sum);}else{scanf("%lld%lld%lld",&x,&y,&z);if(dep[x]<dep[y])swap(x,y);T.chg(1,1,n,dfn[x],low[x],vv[x]^z);vv[x]=z;}}return 0;
}