Submission #481870

# Submission time Handle Problem Language Result Execution time Memory
481870 2021-10-22T04:48:02 Z sberens Mobile (BOI12_mobile) C++17
12 / 100
1000 ms 16288 KB
//#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-5) {
        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

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
            ld s1 = x[i] - dx, e1 = x[i] + dx;
            // can merge in place
            if (!intervals.empty()) {
                auto & [s2, e2] = intervals.back();
                if (max(s1, s2) <= min(e1, e2)){
                    smin(s2, s1);
                    smax(e2, e1);
                } else {
                    intervals.pb({s1, e1});
                }
            } else {
                intervals.pb({s1, e1});
            }
        }
        // check interval spans whole highway
        for (auto [s, e] : intervals) {
            if (s <= 0 && l <= e) return true;
        }
        return false;

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

}
# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 332 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 3 ms 332 KB Output is correct
2 Correct 5 ms 332 KB Output is correct
3 Correct 4 ms 332 KB Output is correct
4 Correct 3 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 5 ms 332 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 73 ms 1524 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 47 ms 1484 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 100 ms 1692 KB Output is correct
2 Correct 93 ms 1712 KB Output is correct
3 Correct 74 ms 1656 KB Output is correct
4 Correct 40 ms 1880 KB Output is correct
5 Incorrect 54 ms 1720 KB Output isn't correct
# Verdict Execution time Memory Grader output
1 Correct 103 ms 1896 KB Output is correct
2 Correct 101 ms 1868 KB Output is correct
3 Correct 92 ms 1896 KB Output is correct
4 Incorrect 40 ms 1892 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 102 ms 1896 KB Output is correct
2 Correct 99 ms 1884 KB Output is correct
3 Correct 85 ms 1900 KB Output is correct
4 Incorrect 44 ms 2008 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 482 ms 8144 KB Output is correct
2 Correct 510 ms 8148 KB Output is correct
3 Correct 510 ms 8252 KB Output is correct
4 Incorrect 198 ms 8252 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 543 ms 8144 KB Output is correct
2 Incorrect 502 ms 8520 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 568 ms 9704 KB Output is correct
2 Correct 597 ms 9704 KB Output is correct
3 Correct 592 ms 9704 KB Output is correct
4 Incorrect 232 ms 9708 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 633 ms 9828 KB Output is correct
2 Incorrect 584 ms 9976 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 669 ms 11284 KB Output is correct
2 Correct 702 ms 11212 KB Output is correct
3 Correct 698 ms 11284 KB Output is correct
4 Incorrect 283 ms 11280 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 705 ms 11280 KB Output is correct
2 Incorrect 649 ms 11728 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 749 ms 12840 KB Output is correct
2 Correct 796 ms 12844 KB Output is correct
3 Correct 785 ms 12844 KB Output is correct
4 Incorrect 313 ms 12860 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 787 ms 12840 KB Output is correct
2 Incorrect 734 ms 13212 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 948 ms 15972 KB Output is correct
2 Execution timed out 1035 ms 15988 KB Time limit exceeded
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 989 ms 16060 KB Output is correct
2 Incorrect 870 ms 16288 KB Output isn't correct
3 Halted 0 ms 0 KB -