답안 #481865

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
481865	2021-10-22T04:13:17 Z	sberens	Mobile (BOI12_mobile)	C++17	70 / 100	1000 ms	47512 KB

mobile

#pragma GCC optimize ("O3,fast-math,inline")

#include <bits/stdc++.h>

#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template <typename K> using hset = gp_hash_table<K, null_type>;
template <typename K, typename V> using hmap = gp_hash_table<K, V>;


using namespace std;

#define all(x) (x).begin(), (x).end()
#define pb push_back
#define eb emplace_back
#define smax(x, y) (x = max(x, y))
#define smin(x, y) (x = min(x, y))

using ld = long double;
using ll = long long;

template <typename T>
using vv = vector<vector<T>>;

using vi = vector<int>;
using ii = array<int, 2>;
using vii = vector<ii>;
using vvi = vv<int>;

using vll = vector<ll>;
using l2 = array<int, 2>;
using vl2 = vector<l2>;
using vvll = vv<ll>;

template <typename T>
using minq = priority_queue<T, vector<T>, greater<T>>;
template <typename T>
using maxq = priority_queue<T>;

const ll M = 1000000007;

#ifndef REFERENCE_DISCRETE_BINARY_SEARCH_H
#define REFERENCE_DISCRETE_BINARY_SEARCH_H


#include <iostream>
#include <functional>


template<typename IN>
IN discrete_binary_search(function<bool(IN)> predicate, IN low = 0, IN high = numeric_limits<IN>::max()) {
    while (fabs(high - low) > 1e-4) {
        IN middle = low + (high - low) / 2; // todo std::midpoint in cpp 2020
        if (predicate(middle))
            high = middle;
        else low = middle;
    }
    return low;
}

#endif //REFERENCE_DISCRETE_BINARY_SEARCH_H

inline bool a_contains_b(array<ld, 2> a,  array<ld, 2> b) {
    return a[0] <= b[0] && b[1] <= a[1];
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n, l;
    cin >> n >> l;
    vll x(n), y(n);
    for (int i = 0; i < n; ++i) {
        cin >> x[i] >> y[i];
    }

    cout << fixed << setprecision(4) <<  discrete_binary_search<ld>([&](ld d) -> bool {
        // is there a point with min distance > d
        // equivalently, is every point within distance d

        vector<array<ld, 2>> intervals;
        intervals.reserve(n);
        // add to intervals
        for (int i = 0; i < n; ++i) {
            if (abs(y[i]) > d) continue;
            ld dx = sqrt(d * d - y[i] * y[i]);
            // get rid of nested intervals
            array<ld, 2> new_interval{x[i] - dx, x[i] + dx};
            while (!intervals.empty() && a_contains_b(new_interval, intervals.back())) {
                intervals.pop_back();
            }
            if (!(!intervals.empty() && a_contains_b(intervals.back(), new_interval)))
                intervals.pb(new_interval);
        }

        // merge intervals
        vector<array<ld, 2>> merged;
        merged.reserve(n);
        for (auto [s, e] : intervals) {
            if (!merged.empty() && s <= merged.back()[1]) smax(merged.back()[1], e);
            else merged.pb({s, e});
        }
        // check interval spans whole highway
        array<ld, 2> highway{0, (ld) l};
        for (auto interval : merged) {
            if (a_contains_b(interval, highway)) return true;
        }
        return false;

    }, 0, sqrt(1e18 + 4 * 1e18 + 1e10)) << '\n';

}

Subtask #1
4.0 / 4.0

#	결과	메모리	Grader output
1	Correct	204 KB	Output is correct
2	Correct	204 KB	Output is correct
3	Correct	204 KB	Output is correct
4	Correct	204 KB	Output is correct

Subtask #2
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	1 ms	204 KB	Output is correct
3	Correct	1 ms	204 KB	Output is correct
4	Correct	0 ms	204 KB	Output is correct

Subtask #3
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	540 KB	Output is correct
2	Correct	4 ms	432 KB	Output is correct
3	Correct	2 ms	332 KB	Output is correct
4	Correct	4 ms	424 KB	Output is correct

Subtask #4
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	5 ms	472 KB	Output is correct
2	Correct	8 ms	552 KB	Output is correct
3	Correct	4 ms	416 KB	Output is correct
4	Correct	4 ms	532 KB	Output is correct

Subtask #5
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	6 ms	492 KB	Output is correct
2	Correct	7 ms	552 KB	Output is correct
3	Correct	4 ms	416 KB	Output is correct
4	Correct	5 ms	524 KB	Output is correct

Subtask #6
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	8 ms	556 KB	Output is correct
2	Correct	8 ms	552 KB	Output is correct
3	Correct	4 ms	428 KB	Output is correct
4	Correct	3 ms	496 KB	Output is correct
5	Correct	5 ms	548 KB	Output is correct

Subtask #7
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	100 ms	3692 KB	Output is correct
2	Correct	82 ms	3148 KB	Output is correct
3	Correct	68 ms	2888 KB	Output is correct
4	Correct	38 ms	2152 KB	Output is correct
5	Correct	29 ms	1264 KB	Output is correct

Subtask #8
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	59 ms	1900 KB	Output is correct
2	Correct	49 ms	2508 KB	Output is correct
3	Correct	49 ms	3276 KB	Output is correct
4	Correct	40 ms	2252 KB	Output is correct
5	Correct	39 ms	2144 KB	Output is correct

Subtask #9
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	142 ms	4504 KB	Output is correct
2	Correct	85 ms	3148 KB	Output is correct
3	Correct	106 ms	3940 KB	Output is correct
4	Correct	39 ms	2344 KB	Output is correct
5	Correct	58 ms	2252 KB	Output is correct

Subtask #10
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	117 ms	3036 KB	Output is correct
2	Correct	90 ms	3168 KB	Output is correct
3	Correct	81 ms	2428 KB	Output is correct
4	Correct	39 ms	2368 KB	Output is correct
5	Correct	60 ms	3944 KB	Output is correct

Subtask #11
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	169 ms	5116 KB	Output is correct
2	Correct	89 ms	3172 KB	Output is correct
3	Correct	74 ms	2532 KB	Output is correct
4	Correct	45 ms	2352 KB	Output is correct
5	Correct	59 ms	3812 KB	Output is correct

Subtask #12
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	864 ms	23936 KB	Output is correct
2	Correct	384 ms	8428 KB	Output is correct
3	Correct	380 ms	8408 KB	Output is correct
4	Correct	190 ms	8660 KB	Output is correct
5	Correct	254 ms	12736 KB	Output is correct

Subtask #13
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	391 ms	8624 KB	Output is correct
2	Correct	687 ms	23676 KB	Output is correct
3	Correct	382 ms	11172 KB	Output is correct
4	Correct	187 ms	8656 KB	Output is correct
5	Correct	228 ms	10948 KB	Output is correct

Subtask #14
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Execution timed out	1035 ms	28640 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #15
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	468 ms	9992 KB	Output is correct
2	Correct	818 ms	28456 KB	Output is correct
3	Correct	434 ms	11792 KB	Output is correct
4	Correct	228 ms	10212 KB	Output is correct
5	Correct	270 ms	12896 KB	Output is correct

Subtask #16
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Execution timed out	1086 ms	33332 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #17
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	536 ms	11612 KB	Output is correct
2	Correct	920 ms	32932 KB	Output is correct
3	Correct	540 ms	15336 KB	Output is correct
4	Correct	266 ms	11844 KB	Output is correct
5	Correct	327 ms	15000 KB	Output is correct

Subtask #18
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Execution timed out	1090 ms	38064 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #19
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	635 ms	13028 KB	Output is correct
2	Execution timed out	1031 ms	37520 KB	Time limit exceeded
3	Halted	0 ms	0 KB	-

Subtask #20
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Execution timed out	1088 ms	47512 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #21
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	760 ms	16240 KB	Output is correct
2	Execution timed out	1101 ms	46716 KB	Time limit exceeded
3	Halted	0 ms	0 KB	-

답안 #481865

Compilation message