Submission #552922

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
552922	2022-04-24T10:12:56 Z	hoanghq2004	Lightning Conductor (POI11_pio)	C++14	100 / 100	121 ms	9364 KB

pio

#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;

const int N = 5e5 + 10;

int n, h[N];

struct Line {
    int a, b, x;
    int operator()(int x) {
        return ceil(sqrt(abs(a - x))) + b;
    }
    long double operator[](int x) {
        return sqrt(abs(a - x)) + b;
    }
    int operator < (const Line& other) const {
        if (x != other.x) return x < other.x;
        if (a != other.a) return a < other.a;
        return b < other.b;
    }
};

int intersect(Line L1, Line L2) {
    int L = max(L1.a, L2.a), R = n + 1;
    while (R - L > 1) {
        int mid = L + R >> 1;
        if (L1[mid] >= L2[mid]) L = mid;
        else R = mid;
    }
    if (L1[L] < L2[L]) return L;
    else return R;
}

int bad(Line L1, Line L2, Line L3) {
    return intersect(L1, L3) <= intersect(L1, L2);
}

int f[N];

int main() {
    ios :: sync_with_stdio(0); cin.tie(0);
    cin >> n;
    for (int i = 1; i <= n; ++i) cin >> h[i];
    vector <Line> convex;
    for (int i = 1, cur = 0; i <= n; ++i) {
        if (i > 1) {
            auto iter = --lower_bound(convex.begin(), convex.end(), (Line){(int)1e9, 0, i});
            f[i] = max(f[i], - h[i] + (*iter)(i));
        }
        //
        if (convex.size() && h[i] <= cur) continue;
        Line L = {i, h[i], 0};
        cur = h[i];
        while (convex.size() >= 2 && bad(convex.end()[-2], convex.back(), L)) convex.pop_back();
        L.x = (convex.empty() ? 1 : intersect(convex.back(), L));
        convex.push_back(L);
    }
    convex.clear();
    reverse(h + 1, h + n + 1);
    for (int i = 1, cur = 0; i <= n; ++i) {
        if (i > 1) {
            auto iter = --lower_bound(convex.begin(), convex.end(), (Line){(int)1e9, 0, i});
            f[n - i + 1] = max(f[n - i + 1], - h[i] + (*iter)(i));
        }
        //
        if (convex.size() && h[i] <= cur) continue;
        Line L = {i, h[i], 0};
        cur = h[i];
        while (convex.size() >= 2 && bad(convex.end()[-2], convex.back(), L)) convex.pop_back();
        L.x = (convex.empty() ? 1 : intersect(convex.back(), L));
        convex.push_back(L);
    }
    for (int i = 1; i <= n; ++i) cout << f[i] << '\n';
}

Compilation message

pio.cpp: In function 'int intersect(Line, Line)':
pio.cpp:35:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   35 |         int mid = L + R >> 1;
      |                   ~~^~~

Subtask #1

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	212 KB	Output is correct

Subtask #2

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	212 KB	Output is correct

Subtask #3

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	340 KB	Output is correct

Subtask #4

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	7 ms	852 KB	Output is correct

Subtask #5

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	1256 KB	Output is correct

Subtask #6

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	15 ms	1224 KB	Output is correct
2	Correct	10 ms	1032 KB	Output is correct
3	Correct	16 ms	1536 KB	Output is correct

Subtask #7

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	23 ms	1612 KB	Output is correct
2	Correct	21 ms	1500 KB	Output is correct
3	Correct	21 ms	2200 KB	Output is correct

Subtask #8

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	48 ms	3292 KB	Output is correct
2	Correct	48 ms	3044 KB	Output is correct
3	Correct	48 ms	3784 KB	Output is correct

Subtask #9

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	75 ms	6628 KB	Output is correct
2	Correct	69 ms	4488 KB	Output is correct
3	Correct	71 ms	6668 KB	Output is correct

Subtask #10

9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	116 ms	9252 KB	Output is correct
2	Correct	91 ms	6264 KB	Output is correct
3	Correct	107 ms	9364 KB	Output is correct

Subtask #11

10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	121 ms	6820 KB	Output is correct
2	Correct	95 ms	6360 KB	Output is correct
3	Correct	96 ms	9336 KB	Output is correct