Submission #1032238

#	Time	Username	Problem	Language	Result	Execution time	Memory
1032238		shmax	Split the Attractions (IOI19_split)	C++17	0 / 100	1 ms	348 KiB

split

#include "split.h"

#include <bits/stdc++.h>

using namespace std;
using i32 = int;
#define int long long
#define len(x) (int)(x.size())
#define inf 1000'000'000'000'000'000LL
#define all(x) x.begin(), x.end()
#define low_bit(x) (x & (-x))

template<typename T>
using vec = vector<T>;

vector<i32> find_split(i32 n, i32 a, i32 b, i32 c, vector<i32> p, vector<i32> q) {
    vec<vec<int>> g(n);
    for (int i = 0; i < len(p); i++) {
        g[p[i]].push_back(q[i]);
        g[q[i]].push_back(p[i]);
    }


    vec<i32> ans(n, 3);
    vec<int> sizes(n);

    vec<pair<i32, i32>> z = {{a, 1},
                             {b, 2},
                             {c, 3}};
    sort(all(z));
    a = z[0].first;
    int ax = z[0].second;
    b = z[1].first;
    int bx = z[1].second;
    int cx = z[2].second;
    std::fill(ans.begin(), ans.end(), cx);
    int splitter = -1;
    int ps;
    vec<int> SZ = {-1, -1};
    vec<int> Tid = {-1, -1};
    vec<bool> used1(n, false);
    function<void(int, int)> calc_sizes = [&](int v, int p) {
        sizes[v] = 1;
        used1[v] = true;
        for (auto u: g[v]) {
            if (u == p) continue;
            if (used1[v]) continue;
            calc_sizes(u, v);
            sizes[v] += sizes[u];
        }
        if (sizes[v] >= a and (n - sizes[v]) >= b) {
            splitter = v;
            SZ[0] = a;
            SZ[1] = b;
            ps = p;
            Tid[0] = ax;
            Tid[1] = bx;
        }
        if (sizes[v] >= b and (n - sizes[v]) >= a) {
            splitter = v;
            SZ[0] = b;
            SZ[1] = a;
            ps = p;
            Tid[0] = bx;
            Tid[1] = ax;
        }
    };
    calc_sizes(0, -1);
    if (splitter == -1) {
        return vec<i32>(n, 0);
    }
    int need = 0;
    int T = 0;
    vec<bool> used(n, false);
    function<void(int, int)> choose = [&](int v, int p) {
        if (need == 0)
            return;
        if (used[v]) return;
        used[v] = true;
        need--;
        ans[v] = T;
        for (auto u: g[v]) {
            if (u == p) continue;
            choose(u, v);
        }
    };
    need = SZ[0];
    T = Tid[0];
    choose(splitter, ps);
    need = SZ[1];
    T = Tid[1];
    choose(0, -1);
    return ans;
}

• Subtask 1: 0 / 7
• Subtask 2: 0 / 11
• Subtask 3: 0 / 22
• Subtask 4: 0 / 24
• Subtask 5: 0 / 36