Submission #609315

#	Time	Username	Problem	Language	Result	Execution time	Memory
609315		lorenzoferrari	Dungeons Game (IOI21_dungeons)	C++17	50 / 100	7033 ms	490656 KiB

dungeons

#include "dungeons.h"
#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
using namespace std;
using vi = vector<int>;
using LL = long long;

constexpr int LG = 25;

struct nd {
    int v;  // final node
    LL inc; // total str increase
    LL ini; // min/max str needed so far
};
nd wjoin(nd a, nd b) {
    nd ans;
    ans.v = b.v;
    ans.inc = a.inc + b.inc;
    ans.ini = max(a.ini, b.ini - a.inc);
    return ans;
}
nd ljoin(nd a, nd b) {
    nd ans;
    ans.v = b.v;
    ans.inc = a.inc + b.inc;
    ans.ini = min(a.ini, b.ini - a.inc);
    return ans;
}

int n;
vi s, p, w, l;

vector<array<nd, LG>> wlift;
vector<array<nd, LG>> llift;

void init(int n, vi s, vi p, vi w, vi l) {
    ::n = n;
    s.push_back(0);
    p.push_back(0);
    w.push_back(n);
    l.push_back(n);
    ::s = s, ::p = p, ::w = w, ::l = l;
    wlift.resize(n+1);
    llift.resize(n+1);
    for (int i = 0; i < n; ++i) {
        wlift[i][0].v = w[i];
        llift[i][0].v = l[i];
        wlift[i][0].inc = s[i];
        llift[i][0].inc = p[i];
        wlift[i][0].ini = s[i];
        llift[i][0].ini = s[i] - 1;
    }
    wlift[n][0] = {n, 0, 0};
    llift[n][0] = {n, 0, 0};
    for (int i = 1; i < LG; ++i) {
        for (int j = 0; j <= n; ++j) {
            int wm = wlift[j][i-1].v;
            int lm = llift[j][i-1].v;
            wlift[j][i] = wjoin(wlift[j][i-1], wlift[wm][i-1]);
            llift[j][i] = ljoin(llift[j][i-1], llift[lm][i-1]);
        }
    }
}

void keep_winning(int& x, LL& z) {
    for (int i = LG-1; i >= 0; --i) {
        if (z >= wlift[x][i].ini) {
            z += wlift[x][i].inc;
            x = wlift[x][i].v;
        }
    }
}

void keep_losing(int& x, LL& z) {
    for (int i = LG-1; i >= 0; --i) {
        if (z <= llift[x][i].ini) {
            z += llift[x][i].inc;
            x = llift[x][i].v;
        }
    }
}

LL simulate(int x, int zi) {
    LL z = zi;
    int i = x;
	while (i != n) {
        keep_winning(i, z);
        keep_losing(i, z);
    }
    return z;
}

• Subtask 1: 11 / 11
• Subtask 2: 26 / 26
• Subtask 3: 13 / 13
• Subtask 4: 0 / 12
• Subtask 5: 0 / 27
• Subtask 6: 0 / 11