Submission #1130076

#	Time	Username	Problem	Language	Result	Execution time	Memory
1130076		Roumak77	Global Warming (NOI13_gw)	C++17	40 / 40	468 ms	12712 KiB

gw

#include <iostream>
#include <vector>
#include <algorithm>
#include <fstream>
using namespace std;

class Element {
private:
  int nothing;
public:
    int val;
    int ind;
    Element(int val, int ind) : val(val), ind(ind) {}
    bool operator<(const Element& o) const {
        return val > o.val; // For descending order
    }
};

bool funt(int mid, std::vector<Element>& T) {
    int islands = 0;
    int index = 0;
    std::vector<bool> v(T.size(), false);
    while (islands < mid && index < T.size()) {
        int currVal = T[index].val;
        while (index < T.size() && T[index].val == currVal) {
            Element curr = T[index];
            v[curr.ind] = true;
            bool left = curr.ind == 0 || !v[curr.ind - 1];
            bool right = curr.ind == v.size() - 1 || !v[curr.ind + 1];
            if (left && right) islands++;
            bool negLeft = curr.ind != 0 && v[curr.ind - 1];
            bool negRight = curr.ind != v.size() - 1 && v[curr.ind + 1];
            if (negLeft && negRight) islands--;
            index++;
        }
    }
    return islands >= mid;
}

int bs(std::vector<Element>& T) {
    int lo = 1;
    int hi = T.size();
    while (lo < hi) {
        int mid = lo + (hi - lo + 1) / 2;
        if (funt(mid, T)) {
            lo = mid;
        } else {
            hi = mid - 1;
        }
    }
    return lo;
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int N;
    std::cin >> N;
    std::vector<Element> Arr;
    for (int i = 0; i < N; i++) {
        int value;
        std::cin >> value;
        Arr.emplace_back(value, i);
    }
    std::sort(Arr.begin(), Arr.end());
    std::cout << bs(Arr) << std::endl;
    return 0;
}

• Subtask 1: 6 / 6
• Subtask 2: 6 / 6
• Subtask 3: 7 / 7
• Subtask 4: 10 / 10
• Subtask 5: 11 / 11