Submission #501916

#	Time	Username	Problem	Language	Result	Execution time	Memory
501916		nighty	Hedgehog Daniyar and Algorithms (IZhO19_sortbooks)	C++14	0 / 100	132 ms	27708 KiB

sortbooks

#include <bits/stdc++.h>

using namespace std;

bool canSort(vector<int>& a, int l, int r, int k) {
    int maxVal = 0;
    for (int i = l; i <= r; ++i) {
        if (maxVal > a[i] && maxVal + a[i] > k) {
            return false;
        }
        maxVal = max(maxVal, a[i]);
    }
    return true;
}

int calcMaxInv(vector<int>& a, int l, int r) {
    int maxVal = 0, res = 0;
    for (int i = l; i <= r; ++i) {
        if (maxVal > a[i]) {
            res = max(res, maxVal + a[i]);
        }
        maxVal = max(maxVal, a[i]);
    }
    return res;
}

const int K = 450;

set<int> s[K];
int maxInverse[K];

int calcMaxInv2(vector<int>& a, int l, int r) {
    int res = calcMaxInv(a, l, min(r, l - l % K + K - 1));
    int maxVal = *max_element(a.begin() + l, a.begin() + l - l % K + K - 1 + 1);
    l = l - l % K + K;
    while (l + K - 1 <= r) {
        res = max(res, maxInverse[l / K]);
        auto it = s[l / K].lower_bound(maxVal);
        if (it != s[l / K].begin()) {
            --it;
            res = max(res, *it + maxVal);
        }
        maxVal = max(maxVal, *s[l / K].rbegin());
        l += K;
    }
    if (l <= r) {
        set<int> tmp;
        for (int i = l; i <= r; ++i) {
            tmp.insert(a[i]);
        }
        auto it = tmp.lower_bound(maxVal);
        if (it != tmp.begin()) {
            --it;
            res = max(res, *it + maxVal);
        }
        res = max(res, calcMaxInv(a, l, r));
    }
    return res;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m;
    cin >> n >> m;
    vector<int> a(n);
    for (auto& i : a) {
        cin >> i;
    }
    for (int i = 0; i < n; ++i) {
        s[i / K].insert(a[i]);
    }
    for (int i = 0; (i + 1) * K - 1 < n; ++i) {
        maxInverse[i] = calcMaxInv(a, i * K, (i + 1) * K - 1);
    }
//    while (m--) {
//        int l, r, k;
//        cin >> l >> r >> k;
//        --l, --r;
//        cout << (calcMaxInv2(a, l, r) <= k) << '\n';
//    }
    return 0;
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 9
• Subtask 3: 0 / 13
• Subtask 4: 0 / 17
• Subtask 5: 0 / 30
• Subtask 6: 0 / 23