CSES Path Queries
// compile: make data
// run: ./data < data.in
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#ifdef LOCAL
#include <debug/codeforces.h>
#define debug(x...) _debug_print(#x, x);
#define Debug(x...) _debug_print_format(#x, x);
#else
#define debug(x...)
#define Debug(x...)
#endif
template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;}
#define VI vector<int>
#define VII vector<vector<int>>
#define VIII vector<vector<vector<int>>>
#define rep(i,a,b) for(int i=(a);i<(int)(b);++i)
#define sz(v) ((int)(v).size())
#define print(...) print_(__VA_ARGS__);
#define FIND(a, x) ((find(a.begin(),a.end(),(x))!=a.end())?1:0)
#define cmin(x,...) x=min({(x), __VA_ARGS__})
#define cmax(x,...) x=max({(x), __VA_ARGS__})
#define INTMAX (int)(9223372036854775807)
#define INF (int)(1152921504606846976)
#define NaN (int)(0x8b88e1d0595d51d1)
#define double long double
#define int long long
#define MAXN 200010

struct tree {
    int n;
    vector<vector<int>> e;
    struct node {
        vector<node*> ch;
        node* parent = nullptr;
        int size, depth, val, sum;
    };
    vector<node> vertex;
    node *root;
    tree(int V) {
        n = V;
        e.resize(n);
        vertex.resize(n);
    }
    void setv(vector<int> &a) {
        rep(i, 0, n) vertex[i].val = a[i];
    }
    void add_edge(int u, int v) {
        e[u].push_back(v), e[v].push_back(u);
    }
    int ind(node *x) {return x - &vertex[0]; }
    void build(int rt = 0) {
        function<void(int, int)> dfs = [&](int u, int pre) {
            vertex[u].size = 1;
            vertex[u].depth = u==ind(root) ? 0 : vertex[u].parent->depth + 1;
            vertex[u].sum = u==ind(root) ? vertex[u].val : vertex[u].parent->sum + vertex[u].val;
            for (int v: e[u]) {
                if (v == pre) continue;
                vertex[u].ch.push_back(&vertex[v]);
                vertex[v].parent = &vertex[u];
                dfs(v, u);
                vertex[u].size += vertex[v].size;
            }
        };
        root = &vertex[rt];
        dfs(rt, -1);
    }
    pair<vector<int>, vector<pair<int, int>>> dfsorder() {
        vector<int> order;
        vector<pair<int, int>> ts(n);
        int cnt = 0;
        function<void(node*)> dfs = [&](node *x) {
            ts[ind(x)].first = cnt++;
            order.push_back(ind(x));
            for (auto y: x->ch) dfs(y);
            order.push_back(ind(x));
            ts[ind(x)].second = cnt++;
        };
        dfs(root);
        return {order, ts};
    }
    void graphviz_dump(int plus = 0, string filename = "graph.dot") {
        FILE *f = fopen(filename.c_str(), "w");
        fprintf(f, "digraph Tree {\n");
        rep(i, 0, n) {
            node *x = &vertex[i];
            fprintf(f, "    %lld;\n");
        }
        rep(i, 0, n) {
            node *x = &vertex[i];
            for (auto y: x->ch) {
                fprintf(f, "    %ld -> %ld;\n", x - &vertex[0], y - &vertex[0]);
            }
        }
        fprintf(f, "}\n");
    }
};

struct bitree {
    int n;
    vector<vector<int>> c;
    vector<int> sum;
    bitree(vector<int> &a) {
        n = sz(a); sum.push_back(0);
        rep(i, 0, n) sum.push_back(sum[i] + a[i]);
        c.resize(2, vector<int>(n+1, 0));
    }
    int lowbit(int x) {return x & (-x); }
    void add(int b, int x, int y) {for (; x <= n; x += lowbit(x)) c[b][x] += y; }
    int get(int b, int x) {int ans = 0; for (; x; x -= lowbit(x)) ans += c[b][x]; return ans; }
    void modify(int p, int k) {modify(p, p, k); }
    void modify(int l, int r, int k) {add(0, l+1, k); add(0, r+2, -k); add(1, l+1, (l+1)*k); add(1, r+2, -(r+2)*k); }
    int query(int p) {return query(p, p); }
    int query(int l, int r) {int ans = sum[r+1] + (r+2)*get(0, r+1) - get(1, r+1); ans -= sum[l] + (l+1)*get(0, l) - get(1, l); return ans; }
};

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);

    int n, q; cin >> n >> q;
    vector<int> a(n);
    rep(i, 0, n) cin >> a[i];
    tree g(n);
    g.setv(a);
    rep(i, 0, n-1) {
        int u, v; cin >> u >> v; --u, --v;
        g.add_edge(u, v);
    }
    g.build(0);
    auto [order, ts] = g.dfsorder();
    rep(i, 0, 2*n) order[i] = g.vertex[order[i]].sum;
    bitree t(order);
    while (q--) {
        int op; cin >> op;
        if (op == 1) {
            int s, x; cin >> s >> x; --s;
            t.modify(ts[s].first, ts[s].second, x-a[s]);
            a[s] = x;
        }
        else if (op == 2) {
            int s; cin >> s; --s;
            cout << t.query(ts[s].first) << '\n';
        }
    }

    return 0;
}
No Comments

Send Comment Edit Comment


				
|´・ω・)ノ
ヾ(≧∇≦*)ゝ
(☆ω☆)
(╯‵□′)╯︵┴─┴
 ̄﹃ ̄
(/ω\)
∠( ᐛ 」∠)_
(๑•̀ㅁ•́ฅ)
→_→
୧(๑•̀⌄•́๑)૭
٩(ˊᗜˋ*)و
(ノ°ο°)ノ
(´இ皿இ`)
⌇●﹏●⌇
(ฅ´ω`ฅ)
(╯°A°)╯︵○○○
φ( ̄∇ ̄o)
ヾ(´・ ・`。)ノ"
( ง ᵒ̌皿ᵒ̌)ง⁼³₌₃
(ó﹏ò。)
Σ(っ °Д °;)っ
( ,,´・ω・)ノ"(´っω・`。)
╮(╯▽╰)╭
o(*////▽////*)q
>﹏<
( ๑´•ω•) "(ㆆᴗㆆ)
😂
😀
😅
😊
🙂
🙃
😌
😍
😘
😜
😝
😏
😒
🙄
😳
😡
😔
😫
😱
😭
💩
👻
🙌
🖕
👍
👫
👬
👭
🌚
🌝
🙈
💊
😶
🙏
🍦
🍉
😣
Source: github.com/k4yt3x/flowerhd
颜文字
Emoji
小恐龙
花!
Previous
Next