Submission #918654

#	Time	Username	Problem	Language	Result	Execution time	Memory
918654		viwlesxq	Xylophone (JOI18_xylophone)	C++17	47 / 100	44 ms	680 KiB

xylophone

#include <bits/stdc++.h>
using namespace std;
#include "xylophone.h"

void solve(int n) {
    vector<int> a(n + 1);
    int min = 1, max = n;
    int lo = 1, hi = n;
    while (lo + 1 < hi) {
        int mid = (lo + hi) / 2;
        if (query(mid, n) == n - 1) lo = mid;
        else hi = mid;
    }
    min = lo;
    lo = 1, hi = n;
    while (lo + 1 < hi) {
        int mid = (lo + hi) / 2;
        if (query(1, mid) == n - 1) hi = mid;
        else lo = mid;
    }
    max = hi;
    a[min] = 1, a[max] = n;
    int last = min, sum = 0;
    bool increasing = true;
    for (int i = min - 1; i > 0; --i) {
        int diff = query(i, last), add = query(i, i + 1);
        if (sum + add != diff) {
            last = i + 1, sum = 0;
            increasing ^= true;
        }
        a[i] = a[i + 1] + (increasing ? add : -add);
        sum += add;
    }
    last = min, sum = 0;
    increasing = true;
    for (int i = min + 1; i < max; ++i) {
        int diff = query(last, i), add = query(i - 1, i);
        if (sum + add != diff) {
            last = i - 1, sum = 0;
            increasing ^= true;
        }
        a[i] = a[i - 1] + (increasing ? add : -add);
        sum += add;
    }
    last = max, sum = 0;
    increasing = false;
    for (int i = max + 1; i <= n; ++i) {
        int diff = query(last, i), add = query(i - 1, i);
        if (sum + add != diff) {
            last = i - 1, sum = 0;
            increasing ^= true;
        }
        a[i] = a[i - 1] + (increasing ? add : -add);
        sum += add;
    }
    for (int i = 1; i <= n; ++i) {
        answer(i, a[i]);
    }
}

• Subtask 1: 11 / 11
• Subtask 2: 36 / 36
• Subtask 3: 0 / 53