제출 #255415

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
255415		ChrisT	Xylophone (JOI18_xylophone)	C++17	100 / 100	146 ms	528 KiB

xylophone

#include<bits/stdc++.h>
#include "xylophone.h"
using namespace std;
bool same[5005]; int diff[5005];
void solve (int n) {
  for (int i = 1; i < n; i++) diff[i] = query(i,i+1);
  for (int i = 1; i + 1 < n; i++) same[i+1] = query(i,i+2) == diff[i] + diff[i+1];
  for (int ree = 0; ree <= 1; ree++) {
    int lt = ree; vector<int> perm(n+1);
    for (int st = 1; st <= n; st++) {
      lt = ree; perm[1] = st;
      for (int j = 2; j <= n; j++) {
        if (lt) perm[j] = perm[j-1] - diff[j-1];
        else perm[j] = perm[j-1] + diff[j-1];
        if (perm[j] < 1 || perm[j] > n) goto fail;
        lt ^= same[j] ^ 1;
      }
      for (int i = 1; i <= n; i++) {
        if (perm[i] == 1) break;
        if (perm[i] == n) goto fail;
      }
      for (int i = 1; i <= n; i++) answer(i,perm[i]);
      return;
      fail:;
    }
  }
  assert(0);
}

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