Submission #1180960

#	Time	Username	Problem	Language	Result	Execution time	Memory
1180960		swishy123	Race (IOI11_race)	C++20	0 / 100	6 ms	14400 KiB

race

#include <iostream>
#include <algorithm>
#include <vector>
#include <random>
#include <chrono>
#include <set>
#include <map>
#include <stack>
#include <functional>
#include <iomanip>
#include <queue>
#include <cassert>
#include <complex>
#include <cstring>
#include <memory>
#include <bitset>
#include <sstream>
#include <cmath>
#include <numeric>
#include <numbers>
#include <fstream>
#include "race.h"

using namespace std;

#ifndef template
#ifndef define
 
#define ll long long
#define ld long double
#define pl pair<ll, ll>
#define pi pair<int, int>
#define nl cout << '\n';
#define x first
#define y second 
#define cbit(x) __builtin_popcountll(x)
#define uid(a, b) uniform_int_distribution<ll>(a, b)(rng) 
#define siz(x) (int)x.size()
 
#endif
 
#ifndef print
void print(size_t x) {cout << x << ' ';}
void print(int x) {cout << x << ' ';}
void print(long long x) {cout << x << ' ';}
void print(float x) {cout << x << ' ';}
void print(long double x) {cout << x << ' ';}
void print(char x) {cout << x << ' ';}
void print(const char* x) {cout << x << ' ';}
void print(bool x) {cout << x << ' ';}
void print(string &x) {cout << x << ' ';}
 
template<typename T, typename V>
void print(pair<T, V> &p) {print(p.x); print(p.y);}
template<typename T>
void print(vector<T> v) {for (int i = 0; i < v.size(); i++) print(v[i]);}
template<typename T>
void print(vector<vector<T>> v) {
    for (int i = 0; i < v.size(); i++){
        for (int j = 0; j < v[i].size(); j++)
            print(v[i][j]);
        nl;
    }
}
template <typename T, typename... V>
void print(T t, V&&... v) {print(t); print(v...);}
 
#endif
 
#ifndef read
void read(int &x) {cin >> x;}
void read(long long &x) {cin >> x;}
void read(unsigned &x) {cin >> x;}
void read(unsigned long long &x) {cin >> x;}
void read(float &x) {cin >> x;}
void read(long double &x) {cin >> x;}
void read(char &x) {cin >> x;}
void read(string &x) {cin >> x;}
void read(bool &x) {cin >> x;}
 
template<typename T> 
void read(vector<T> &v) {
    for (int i = 0; i < v.size(); i++)
        read(v[i]);
}
template <typename T, typename... V>
void read(T &t, V&... v) {read(t); read(v...);}
#endif
 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
template<class T> bool maxi(T& a, const T& b) {
    return a < b ? a = b, 1 : 0;
}
template<class T> bool mini(T& a, const T& b) {
    return a > b ? a = b, 1 : 0;
}
template<class... Args>
auto vec(size_t n, Args&&... args) {
    if constexpr(sizeof...(args) == 1)
        return vector(n, args...);
    else
        return vector(n, vec(args...));
}

#endif

using namespace std;
const ll inf = 1e15;
const ll def = 2e5+1;
const ll mod = 998244353;

set<pl> s[def];
vector<pl> edg[def];
ll h[def], wi[def];
ll res = inf;

void dfs(int u, int pre, ll k, ll crr, ll height){
    s[u].insert({wi[u], h[u]});
    for (auto [v, w] : edg[u]){
        if (v == pre)
            continue;
        h[v] = h[u] + 1;
        wi[v] = wi[u] + w;
        
        dfs(v, u, k, crr + w, height + 1);
        if (s[v].size() > s[u].size())
            s[u].swap(s[v]);
        for (auto [wv, len] : s[v]){
            ll need = k + 2 * crr - wv;
            auto it = s[u].lower_bound({need, -inf});

            if ((*it).x == need)
                mini(res, (*it).y + len - 2 * height);
        }
        for (auto [wv, len] : s[v]){
            auto it = s[u].lower_bound({wv, -inf});
            if ((*it).x == wv && len < (*it).y){
                s[u].erase(*it);
                s[u].insert({wv, len});
            }
            else
                s[u].insert({wv, len});
        }
    }
    ll need = k + crr;
    auto it = s[u].lower_bound({need, -inf});
    if ((*it).x == need)
        mini(res, (*it).y - crr);
}

/*
wi_u + wi_v - 2 * crr = k
wi_v = k + 2 * crr - wi_u
*/

int best_path(int N, int K, int H[][2], int L[]){
    for (int i = 0; i < N - 1; i++){
        int u = H[i][0], v = H[i][1], w = L[i];
        edg[u].push_back({v, w});
        edg[v].push_back({u, w});
    }
    dfs(0, -1, K, 0, 0);
    if (res == inf)
        return -1;
    else
        return res;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 22
• Subtask 4: 0 / 57