CF383C Propagating tree （线段树，欧拉序）

\(tag\)没开够\(WA\)了一发。。。

求出\(dfs\)序，然后按深度分类更新与查询。

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#define R(a,b,c) for(register int  a = (b); a <= (c); ++ a)
#define nR(a,b,c) for(register int  a = (b); a >= (c); -- a)
#define Max(a,b) ((a) > (b) ? (a) : (b))
#define Min(a,b) ((a) < (b) ? (a) : (b))
#define Fill(a,b) memset(a, b, sizeof(a))
#define Abs(a) ((a) < 0 ? -(a) : (a))
#define Swap(a,b) a^=b^=a^=b
#define ll long long

#define ON_DEBUG

#ifdef ON_DEBUG

#define D_e_Line printf("\n\n----------\n\n")
#define D_e(x)  cout << #x << " = " << x << endl
#define Pause() system("pause")
#define FileOpen() freopen("in.txt","r",stdin);

#else

#define D_e_Line ;
#define D_e(x)  ;
#define Pause() ;
#define FileOpen() ;

#endif

struct ios{
    template<typename ATP>ios& operator >> (ATP &x){
        x = 0; int f = 1; char c;
        for(c = getchar(); c < '0' || c > '9'; c = getchar()) if(c == '-')  f = -1;
        while(c >= '0' && c <= '9') x = x * 10 + (c ^ '0'), c = getchar();
        x*= f;
        return *this;
    }
}io;
using namespace std;

const int N = 200007;

struct Edge{
	int nxt, pre;
}e[N << 1];
int head[N], cntEdge;
inline void add(int u, int v){
	e[++cntEdge] = (Edge){ head[u], v}, head[u] = cntEdge;
}

int dep[N], L[N], R[N], dfnIndex;
inline void DFS(int u, int fa){
	dep[u] = dep[fa] + 1, L[u] = ++dfnIndex;
	for(register int i = head[u]; i; i = e[i].nxt){
		int v = e[i].pre;
		if(v == fa) continue;
		DFS(v, u);
	}
	R[u] = dfnIndex;
}

int val[N];

#define lson rt << 1, l, mid
#define rson rt << 1 | 1, mid + 1, r
int t[N << 2], tag[N << 3];
inline void Pushup(int rt){
	t[rt] = t[rt << 1] + t[rt << 1 | 1];
}
inline void Pushdown(int rt, int l, int r){
	if(!tag[rt]) return;
	tag[rt << 1] += tag[rt];
	tag[rt << 1 | 1] += tag[rt];
	int mid = (l + r) >> 1;
	t[rt << 1] += (mid - l + 1) * tag[rt];
	t[rt << 1 | 1] += (r - mid) * tag[rt];
	tag[rt] = 0;
}
inline void Updata(int rt, int l, int r, int L, int R, int w){
	if(L <= l && r <= R){
		tag[rt] += w;
		t[rt] += (r - l + 1) * w;
		return;
	}
	Pushdown(rt, l, r);
	int mid = (l + r) >> 1;
	if(L <= mid)
		Updata(lson, L, R, w);
	if(R > mid)
		Updata(rson, L, R, w);
	Pushup(rt);
}
inline int Query(int rt, int l, int r, int x){
	if(l == r){
		return t[rt];
	}
	Pushdown(rt, l, r);
	int mid = (l + r) >> 1;
	if(x <= mid)
		return Query(lson, x);
	else
		return Query(rson, x);
}
int main(){
//FileOpen();
	int n, m;
	io >> n >> m;
	R(i,1,n){
		io >> val[i];
	}
	R(i,2,n){
		int u, v;
		io >> u >> v;
		add(u, v);
		add(v, u);
	}

	DFS(1, 0);

	while(m--){
		int opt;
		io >> opt;
		if(opt == 1){
			int x, w;
			io >> x >> w;
			Updata(1, 1, n, L[x], R[x], dep[x] & 1 ? w : -w);
		}
		else{
			int x;
			io >> x;
			printf("%d\n", val[x] + Query(1, 1, n, L[x]) * (dep[x] & 1 ? 1 : -1));
		}
	}

	return 0;
}