Submission #964218

#	Time	Username	Problem	Language	Result	Execution time	Memory
964218		vjudge1	Election Campaign (JOI15_election_campaign)	C++17	100 / 100	219 ms	44916 KiB

election_campaign

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

#define int long long
#define FOR(i, a, b) for (int i = a; i <= b; i++)
#define FORD(i, a, b) for (int i = b; i >= a; i --)
#define REP(i, n) for (int i = 0; i < n; ++i)
#define REPD(i, n) for (int i = n - 1; i >= 0; --i)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)

constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

void setupIO(){
    #define name "Whisper"
    //Phu Trong from Nguyen Tat Thanh High School for gifted student
    srand(time(NULL));
    cin.tie(nullptr)->sync_with_stdio(false); cout.tie(nullptr);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    cout << fixed << setprecision(10);
}

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
const int MAX = 1e5 + 5;
int numNode, numQuery;

struct Edge{
    int u, v;
    Edge(){}
    Edge(int _u, int _v): u(_u), v(_v){}

    int other(int x){ return (x ^ u ^ v); }
} edge[MAX];

vector<int> G[MAX];


int tin[MAX], tout[MAX], cnt = 0;
int up[MAX][21], depth[MAX], par[MAX];

void pre_dfs(int u, int p = -1){
    tin[u] = ++cnt;
    for (int &i : G[u]){
        int v = edge[i].other(u);
        if(v ^ p){
            depth[v] = depth[u] + 1;
            par[v] = u;
            up[v][0] = u;
            for (int i = 1; i <= 20; ++i) up[v][i] = up[up[v][i - 1]][i - 1];
            pre_dfs(v, u);

        }
    }
    tout[u] = cnt;
}

int lca(int u, int v){
    if (depth[u] < depth[v]) swap(u, v);
    int dis = depth[u] - depth[v];
    for (int i = 0; MASK(i) <= dis; ++i) if(BIT(dis, i))
        u = up[u][i];
    if (u == v) return u;
    int k = 31 - __builtin_clz(depth[v]);
    for (int i = k; i >= 0; --i) if(up[u][i] != up[v][i]){
        u = up[u][i], v = up[v][i];
    }
    return up[u][0];
}

vector<tuple<int, int, int>> q[MAX];
int ndp[MAX], dp[MAX];


struct FenwickTree{
    int n;
    vector<int> f;
    FenwickTree(int _n = 0){
        this -> n = _n;
        f.resize(n + 5);
    }
    void modify(int p, int val){
        for (; p <= n; p += p & (-p)) f[p] += val;
    }
    int query(int p){
        int res = 0;
        for (; p > 0; p -= p & (-p)) res += f[p];
        return res;
    }
    void modify(int l, int r, int val){
        modify(l, val); modify(r + 1, -val);
    }
} fen;

void dfs(int u, int p = -1){
    for (int &i : G[u]){
        int v = edge[i].other(u);
        if(v ^ p){
            dfs(v, u);
            ndp[u] += dp[v];
        }
    }
    dp[u] = ndp[u]; // not choose any segment

    for (tuple<int, int, int>&x : q[u]){
        int nodeu, nodev, c; tie(nodeu, nodev, c) = x;
        maximize(dp[u], fen.query(tin[nodeu]) + fen.query(tin[nodev]) + c + ndp[u]);
    }

    fen.modify(tin[u], tout[u], ndp[u] - dp[u]);
}
void Whisper(){
    cin >> numNode;

    for (int i = 1; i < numNode; ++i){
        cin >> edge[i].u >> edge[i].v;
        G[edge[i].u].emplace_back(i);
        G[edge[i].v].emplace_back(i);
    }
    //dp on tree

    pre_dfs(1);
    cin >> numQuery;

    for (int i = 1; i <= numQuery; ++i){
        int u, v, c; cin >> u >> v >> c;
        int p = lca(u, v);
        q[p].emplace_back(u, v, c);
    }

    fen = FenwickTree (numNode);
    dfs(1);
    cout << dp[1];
}


signed main(){
    setupIO();
    int Test = 1;
//    cin >> Test;
    for ( int i = 1 ; i <= Test ; i++ ){
        Whisper();
        if (i < Test) cout << '\n';
    }
}

• Subtask 1: 10 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 30 / 30
• Subtask 5: 10 / 10
• Subtask 6: 40 / 40