CF Edu54 E. Vasya and a Tree DFS+树状数组

Vasya and a Tree

题意:

   给定一棵树,对树有3e5的操作,每次操作为,把树上某个节点的不超过d的子节点都加上值x;

思路:

  多开一个vector记录每个点上的操作。dfs这颗树,同时以深度开一个树状数组,踩到u节点的时候,给数组add(deep, x); add(min(maxn,deep + op[u][i].fi + 1), - op[u][i].se);

搜索下去,反回前得到这个节点的答案,并消去这个点的影响。

//#pragma GCC optimize(3)
//#pragma comment(linker, "/STACK:102400000,102400000")  //c++
// #pragma GCC diagnostic error "-std=c++11"
// #pragma comment(linker, "/stack:200000000")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <algorithm>
#include  <iterator>
#include  <iostream>
#include   <cstring>
#include   <cstdlib>
#include   <iomanip>
#include    <bitset>
#include    <cctype>
#include    <cstdio>
#include    <string>
#include    <vector>
#include     <stack>
#include     <cmath>
#include     <queue>
#include      <list>
#include       <map>
#include       <set>
#include   <cassert>

using namespace std;
#define lson (l , mid , rt << 1)
#define rson (mid + 1 , r , rt << 1 | 1)
#define debug(x) cerr << #x << " = " << x << "\n";
#define pb push_back
#define pq priority_queue



typedef long long ll;
typedef unsigned long long ull;
//typedef __int128 bll;
typedef pair<ll ,ll > pll;
typedef pair<int ,int > pii;
typedef pair<int,pii> p3;

//priority_queue<int> q;//这是一个大根堆q
//priority_queue<int,vector<int>,greater<int> >q;//这是一个小根堆q
#define fi first
#define se second
//#define endl '\n'

#define OKC ios::sync_with_stdio(false);cin.tie(0)
#define FT(A,B,C) for(int A=B;A <= C;++A)  //用来压行
#define REP(i , j , k)  for(int i = j ; i <  k ; ++i)
#define max3(a,b,c) max(max(a,b), c);
//priority_queue<int ,vector<int>, greater<int> >que;

const ll mos = 0x7FFFFFFF;  //2147483647
const ll nmos = 0x80000000;  //-2147483648
const int inf = 0x7f7f7f7f;
const ll inff = 0x3f3f3f3f3f3f3f3f; //18
const int mod = 1e8+7;
const double esp = 1e-8;
const double PI=acos(-1.0);
const double PHI=0.61803399;    //黄金分割点
const double tPHI=0.38196601;


template<typename T>
inline T read(T&x){
    x=0;int f=0;char ch=getchar();
    while (ch<'0'||ch>'9') f|=(ch=='-'),ch=getchar();
    while (ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();
    return x=f?-x:x;
}


/*-----------------------showtime----------------------*/

        const int maxn = 3e5+9;
        ll ans[maxn];
        vector<pii> op[maxn];
        vector<int>mp[maxn];
        ll sum[maxn];

        int lowbit(int x){
            return x & (-x);
        }

        void add(int x,int val){
            while(x < maxn){
                sum[x] += val;
                x += lowbit(x);
            }
        }

        ll getsum(int x){
            ll res = 0;
            while(x > 0){
                res += sum[x];
                x -= lowbit(x);
            }
            return res;
        }
        void dfs(int u, int fa, int deep){

            for(int i=0; i<op[u].size(); i++){
                add(deep, op[u][i].se);
                add(min(maxn,deep + op[u][i].fi + 1), -1ll*op[u][i].se);
            }

            for(int i=0; i<mp[u].size(); i++){
                int v = mp[u][i];
                if(v == fa)continue;
                dfs(v, u, deep + 1);
            }

            ans[u] = getsum(deep);


            for(int i=0; i<op[u].size(); i++){
                add(deep, -1ll*op[u][i].se);
                add(min(maxn,deep + op[u][i].fi + 1), op[u][i].se);
            }
        }
int main(){

        int n,m;  scanf("%d", &n);
        for(int i=1; i<n; i++){
            int u,v;
            scanf("%d%d", &u, &v);
            mp[u].pb(v);
            mp[v].pb(u);
        }
        scanf("%d", &m);
        for(int i=1; i<=m; i++){
            int v,d,x;
            scanf("%d%d%d", &v, &d, &x);
            op[v].pb(pii(d,x));
        }

        dfs(1, -1, 1);
        for(int i=1; i<=n; i++) printf("%lld ", ans[i]);
        puts("");
        return 0;
}
CFeduE

 

posted @ 2018-11-15 16:31  ckxkexing  阅读(171)  评论(0编辑  收藏  举报