正题

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题目大意

要求支持路径加和求和，子树加和求和

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解题思路

树剖不解释

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$code$

#include<cstdio>
#include<algorithm>
using namespace std;
const int N=200000;
int tot,cnt,n,m,s,p,ls[N],pw[N],id[N];
int siz[N],dep[N],f[N],son[N],seg[N],top[N];
struct treenode{int l,r,lazy,val;
};
struct LineTree{treenode t[N*2];void build(int x,int l,int r){t[x].l=l;t[x].r=r;if(l==r){t[x].val=pw[id[l]]%p;return;}int mid=(l+r)>>1;build(x*2,l,mid);build(x*2+1,mid+1,r);t[x].val=(t[x*2].val+t[x*2+1].val)%p;}void downdata(int x){if(t[x].lazy){(t[x*2].lazy+=t[x].lazy)%=p;(t[x*2].val+=t[x].lazy*(t[x*2].r-t[x*2].l+1))%=p;(t[x*2+1].lazy+=t[x].lazy)%=p;(t[x*2+1].val+=t[x].lazy*(t[x*2+1].r-t[x*2+1].l+1))%=p;t[x].lazy=0;}}void change(int x,int l,int r,int num){if(t[x].l==l&&t[x].r==r){(t[x].val+=num*(t[x].r-t[x].l+1))%=p;(t[x].lazy+=num)%=p;return;}downdata(x);int mid=(t[x].l+t[x].r)>>1;if(r<=mid) change(x*2,l,r,num);else if(l>mid) change(x*2+1,l,r,num);else change(x*2,l,mid,num),change(x*2+1,mid+1,r,num);t[x].val=(t[x*2].val+t[x*2+1].val)%p;}int find(int x,int l,int r){if(t[x].l==l&&t[x].r==r)return t[x].val;downdata(x);int mid=(t[x].l+t[x].r)>>1;if(r<=mid) return find(x*2,l,r);else if(l>mid) return find(x*2+1,l,r);else return (find(x*2,l,mid)+find(x*2+1,mid+1,r))%p;    }
}LT;
struct edge_node{int to,next;
}a[N*2];
void addl(int x,int y)
{a[++tot].to=y;a[tot].next=ls[x];ls[x]=tot;
}
void dfs1(int x,int fa)
{siz[x]=1;for(int i=ls[x];i;i=a[i].next){int y=a[i].to;if(y==fa) continue;dep[y]=dep[x]+1;f[y]=x;dfs1(y,x);siz[x]+=siz[y];if(siz[y]>siz[son[x]])son[x]=y;}
}
void dfs2(int x,int fa)
{seg[x]=++cnt;id[cnt]=x;if(son[x]){top[son[x]]=top[x];dfs2(son[x],x);}for(int i=ls[x];i;i=a[i].next){int y=a[i].to;if(y==fa||y==son[x]) continue;top[y]=y;dfs2(y,x);}
}
void path_change(int x,int y,int z)
{while(top[x]!=top[y]){if(dep[top[x]]<dep[top[y]]) swap(x,y);LT.change(1,seg[top[x]],seg[x],z);x=f[top[x]];}if(dep[x]>dep[y]) swap(x,y);LT.change(1,seg[x],seg[y],z);return;
}
int path_ask(int x,int y)
{int ans=0;while(top[x]!=top[y]){if(dep[top[x]]<dep[top[y]]) swap(x,y);(ans+=LT.find(1,seg[top[x]],seg[x]))%=p;x=f[top[x]];}if(dep[x]>dep[y]) swap(x,y);(ans+=LT.find(1,seg[x],seg[y]))%=p;return ans;
}
int main()
{scanf("%d%d%d%d",&n,&m,&s,&p);for(int i=1;i<=n;i++)scanf("%d",&pw[i]);for(int i=1;i<n;i++){int x,y;scanf("%d%d",&x,&y);addl(x,y);addl(y,x);}dfs1(s,0);top[s]=s;dfs2(s,0);LT.build(1,1,n);for(int i=1;i<=m;i++){int t,x,y,z;scanf("%d%d",&t,&x);if(t==1){scanf("%d%d",&y,&z);path_change(x,y,z);}if(t==2){scanf("%d",&y);printf("%d\n",path_ask(x,y));}if(t==3){scanf("%d",&z);LT.change(1,seg[x],seg[x]+siz[x]-1,z);}if(t==4){printf("%d\n",LT.find(1,seg[x],seg[x]+siz[x]-1));}}
}