Submission #915100

#	Time	Username	Problem	Language	Result	Execution time	Memory
915100		RaresFelix	Fireworks (APIO16_fireworks)	C++17	7 / 100	1 ms	600 KiB

fireworks

#include <bits/stdc++.h>
//#pragma GCC optimize("O3")
//#pragma GCC target("avx,avx2,fma")

#define sz(x) int((x).size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()

using namespace std;
using ll = long long;
using ld = long double;  // or double, if TL is tight
using str = string; 
using ii = pair<int, int>;
using pl = pair<ll, ll>;
using vi = vector<int>;
using vll = vector<ll>;

struct fun {
    ll ct = 0;
    vll V;
    fun &operator+=(const fun &rhs) {
        ct += rhs.ct;
        for(auto it : rhs.V)
            V.push_back(it);
        return *this;
    }

    fun clean(ll w) {
        sort(all(V));
        deque<ll> D;
        for(auto it : V) D.push_back(it);
        V.clear();
        while(D.size() > 2) {
            ct += D.back() - D.front();
            D.pop_back();
            D.pop_front();
        }
        for(auto it : D) V.push_back(it + w);
        if(V.size() == 1) V.push_back(V.back());
        return *this;
    }

    ll eval() {
        sort(all(V));
        deque<ll> D;
        for(auto it : V) D.push_back(it);
        V.clear();
        while(!D.empty()) {
            ct += D.back() - D.front();
            D.pop_back();
            if(!D.empty())
                D.pop_front();
        }
        return ct;
    }
    ll ev(ll i) {
        ll val = ct;
        for(auto it : V) val += abs(it - i);
        return val;
    }
};

struct tree {
    ll n;
    ll limExp;
    vi par;
    vector<vector<ii> > L, G;
    tree(ll N, ll LimExpl) : n(N), limExp(LimExpl), par(N), L(N), G(N) {}

    void add_edge(ll u, ll v, ll w) {
        L[u].push_back({v, w});
        L[v].push_back({u, w});
    }

    void init() {
        function<fun(ll, ll)> dfs = [&](ll u, ll p) {
            if(u >= limExp) { /// frunza cu bomba, nu face nimic 
                fun re;
                re.V.push_back(0);
                re.V.push_back(0);
                return re; 
            }
            fun re;
            for(auto [it, w] : L[u])
                if(it != p) {
                    auto fiu = dfs(it, u).clean(w);
                    re += fiu;
                }
            return re;
        };
        cout << dfs(0, -1).eval() / 2 << "\n";
    }
};



int main() {
    cin.tie(0);
    ios_base::sync_with_stdio(0);
    ll n, m;
    cin >> n >> m;
    tree T(n + m, n);
    for(ll i = 1; i < n + m; ++i) {
        ll u, v, w;
        cin >> u >> w;
        --u;
        T.add_edge(u, i, w);
    }
    T.init();
    return 0;
}

Compilation message (stderr)

fireworks.cpp: In function 'int main()':
fireworks.cpp:104:15: warning: unused variable 'v' [-Wunused-variable]
  104 |         ll u, v, w;
      |               ^

• Subtask 1: 7 / 7
• Subtask 2: 0 / 19
• Subtask 3: 0 / 29
• Subtask 4: 0 / 45