답안 #481862

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
481862	2021-10-22T04:09:23 Z	sberens	Mobile (BOI12_mobile)	C++17	70 / 100	1000 ms	47328 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({x[i] - dx, x[i] + dx});
        }

        // 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
        return any_of(all(merged), [&](array<ld, 2> interval) -> bool {return a_contains_b(interval, {0, (ld) l});});

    }, 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	1 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	368 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	480 KB	Output is correct
2	Correct	8 ms	556 KB	Output is correct
3	Correct	3 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	9 ms	552 KB	Output is correct
3	Correct	5 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	3 ms	428 KB	Output is correct
4	Correct	3 ms	656 KB	Output is correct
5	Correct	4 ms	420 KB	Output is correct

Subtask #7
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	102 ms	3696 KB	Output is correct
2	Correct	75 ms	3208 KB	Output is correct
3	Correct	82 ms	2880 KB	Output is correct
4	Correct	39 ms	2148 KB	Output is correct
5	Correct	26 ms	1280 KB	Output is correct

Subtask #8
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	44 ms	1944 KB	Output is correct
2	Correct	48 ms	2516 KB	Output is correct
3	Correct	55 ms	3268 KB	Output is correct
4	Correct	38 ms	2236 KB	Output is correct
5	Correct	36 ms	2116 KB	Output is correct

Subtask #9
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	153 ms	4680 KB	Output is correct
2	Correct	90 ms	3152 KB	Output is correct
3	Correct	112 ms	3988 KB	Output is correct
4	Correct	37 ms	2300 KB	Output is correct
5	Correct	55 ms	2248 KB	Output is correct

Subtask #10
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	107 ms	3044 KB	Output is correct
2	Correct	95 ms	3148 KB	Output is correct
3	Correct	70 ms	2448 KB	Output is correct
4	Correct	37 ms	2300 KB	Output is correct
5	Correct	57 ms	3940 KB	Output is correct

Subtask #11
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	187 ms	5036 KB	Output is correct
2	Correct	76 ms	3148 KB	Output is correct
3	Correct	63 ms	2588 KB	Output is correct
4	Correct	39 ms	2360 KB	Output is correct
5	Correct	63 ms	3820 KB	Output is correct

Subtask #12
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	969 ms	24088 KB	Output is correct
2	Correct	323 ms	8436 KB	Output is correct
3	Correct	305 ms	8396 KB	Output is correct
4	Correct	183 ms	8648 KB	Output is correct
5	Correct	238 ms	12748 KB	Output is correct

Subtask #13
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	321 ms	8592 KB	Output is correct
2	Correct	730 ms	23700 KB	Output is correct
3	Correct	332 ms	11148 KB	Output is correct
4	Correct	178 ms	8644 KB	Output is correct
5	Correct	220 ms	10960 KB	Output is correct

Subtask #14
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Execution timed out	1091 ms	28648 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #15
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	377 ms	9960 KB	Output is correct
2	Correct	850 ms	28304 KB	Output is correct
3	Correct	364 ms	11804 KB	Output is correct
4	Correct	213 ms	10212 KB	Output is correct
5	Correct	255 ms	12916 KB	Output is correct

Subtask #16
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Execution timed out	1089 ms	33344 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #17
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	438 ms	11504 KB	Output is correct
2	Correct	958 ms	32944 KB	Output is correct
3	Correct	547 ms	15460 KB	Output is correct
4	Correct	253 ms	11920 KB	Output is correct
5	Correct	335 ms	14984 KB	Output is correct

Subtask #18
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Execution timed out	1088 ms	37940 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #19
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	474 ms	13040 KB	Output is correct
2	Execution timed out	1081 ms	37544 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	1080 ms	47328 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #21
0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	633 ms	16364 KB	Output is correct
2	Execution timed out	1085 ms	46700 KB	Time limit exceeded
3	Halted	0 ms	0 KB	-

답안 #481862

Compilation message