Submission #894607

#	Time	Username	Problem	Language	Result	Execution time	Memory
894607		lunaTu	Xylophone (JOI18_xylophone)	C++17	100 / 100	64 ms	760 KiB

xylophone

#include <bits/stdc++.h>
#define ff first
#define ss second
#define all(x) x.begin(), x.end()
#include "xylophone.h"
typedef long long ll;
using namespace std;

bool solve2(int n, vector<pair<int, int>>& g) {
    map<int, int> d;

    vector<int> a(n + 1);

    a[1] = 0;
    a[2] = g[2].ss;

    d[0] = 1;
    d[a[2]] = 2;

    for (int i = 3; i <= n; i++) {
        int x = g[i].ff, y = g[i].ss;

        int r = abs(a[i - 2] - a[i - 1]);

        if (a[i - 2] < a[i - 1]) {
            if (x != r  && x != y) a[i] = a[i - 2] + x;
            else a[i] = a[i - 1] - y;
        }
        else {
            if (x != r && x != y) a[i] = a[i - 2] - x;
            else a[i] = a[i - 1] + y;
        }

        if (d[a[i]]) return 0;

        d[a[i]] = i;
    }

    if ((*d.begin()).ss > (*d.rbegin()).ss) return 0;

    int i = 1;
    for (auto [x, y] : d) {
        answer(y, i);
        i++;
    }

    return 1;
}

void solve(int N) {
    vector<pair<int, int>> g(N + 1);
    g[2].ss = query(1, 2);

    for (int i = 3; i <= N; i++) {
        g[i].ff = query(i - 2, i);
        g[i].ss = query(i - 1, i);
    }

    if (solve2(N, g)) return;

    g[2].ss *= -1;

    if (solve2(N, g)) return;
}

• Subtask 1: 11 / 11
• Subtask 2: 36 / 36
• Subtask 3: 53 / 53