| # | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
|---|---|---|---|---|---|---|---|
| 1310735 | theiulius | 동굴 (IOI13_cave) | C++20 | 0 ms | 0 KiB |
#include <bits/stdc++.h>
using namespace std;
#define int long long
#include "cave.h"
void exploreCave(int N) {
int n = N;
vector<int> used(n, 0); // which switches already fixed (mp in your code)
vector<int> a(n, 0), b(n, -1);
for (int i = 0; i < n; ++i) {
// set all unfixed switches to 0 and query to determine berk
for (int j = 0; j < n; ++j) if (!used[j]) a[j] = 0;
int x = tryCombination(a);
int berk = (x > i || x == -1) ? 0 : 1;
// build list of unused switches (indices)
vector<int> unused;
unused.reserve(n);
for (int j = 0; j < n; ++j) if (!used[j]) unused.push_back(j);
// binary search on positions inside `unused`
int L = 0, R = (int)unused.size() - 1;
int pos = -1;
while (L <= R) {
int mid = (L + R) >> 1;
// set first mid+1 unused switches to berk, rest to 1^berk
for (int k = 0; k <= mid; ++k) a[unused[k]] = berk;
for (int k = mid + 1; k < (int)unused.size(); ++k) a[unused[k]] = (1 ^ berk);
x = tryCombination(a);
if (x > i || x == -1) {
pos = mid; // possible answer in unused[pos]
R = mid - 1;
} else {
L = mid + 1;
}
}
// pos must be valid; but just in case (defensive), handle -1
if (pos == -1) pos = (int)unused.size() - 1;
int ans = unused[pos];
b[ans] = i;
used[ans] = 1;
a[ans] = berk; // fix this switch permanently
}
answer(a.data(), b.data());
}