Submission #848892

#	Time	Username	Problem	Language	Result	Execution time	Memory
848892		Itamar	Radio Towers (IOI22_towers)	C++17	100 / 100	1632 ms	55100 KiB

towers

#include <vector>
#include <cassert>
#include <cstdio>
#include <algorithm>
#include <vector>
using namespace std;
#define vi vector<int>
#include <set>
vi st;
const int siz = 1e5;
int h[siz];
int d;
#define pi pair<int,int>
#pragma warning(disable : 4996)
struct node {
    int l, r, mid, maxi,ans;
    vector<pi> v;
    vi vd;
    node* sl, * sr,*t=NULL;
    node(int li, int ri) {
        l = li, r = ri, mid = (l + r) / 2,v.resize(r-l+2),vd.resize(r-l+2);
        vd[0] = 1e9;
        if (l < r) {
            sl = new node(l, mid);
            sr = new node(mid + 1, r);
            maxi = max(sl->maxi, sr->maxi);
        }
        else {
            maxi = h[l];
            ans = 1;
            v[1] = { l,l };
            vd[1] = 1e9;
        }
    }
    int qm(int a, int b) {
        if (a > b)return 0;
        if (a > r || b < l)return 0;
        if (a <= l && b >= r)return maxi;
        return max(sl->qm(a, b), sr->qm(a, b));
    }
    void calc(node* top) {
        t = top;
        if (l < r) {
            sl->calc(top), sr->calc(top);
            vector<pi> vec;
            for (int i = 1; i <= mid - l + 1; i++)vec.push_back({ sl->vd[i], i });
            for (int i = 1; i <= r-mid; i++)vec.push_back({ sr->vd[i], -i });
            sort(vec.begin(), vec.end());
            reverse(vec.begin(), vec.end());
            int maxi1 = 0, maxi2 = 0;
            for (int i = 0; i < vec.size(); i++) {
                if (vec[i].second>=0)maxi1++;
                else maxi2++;
                int op = min(vec[i].first, t->qm(sl->v[maxi1].second + 1, sr->v[maxi2].first - 1)- max(h[sl->v[maxi1].second],h[sr->v[maxi2].first]));
                if (maxi1 && maxi2 && vd[maxi1 + maxi2] < op) {
                    vd[maxi1 + maxi2] = op;
                    v[maxi1 + maxi2] = { sl->v[maxi1].first,sr->v[maxi2].second };
                }
                if (maxi1 && maxi2 && vd[maxi1 + maxi2 - 1] < vec[i].first) {
                    vd[maxi1 + maxi2 - 1] = vec[i].first;
                    v[i].first = sl->v[maxi1].first;
                    v[i].second = sr->v[maxi2].second;
                    if (sl->v[maxi1].first == sl->v[maxi1].second && h[sl->v[maxi1].first] > h[sr->v[maxi2].first])v[i].first = sr->v[maxi2].first;
                    else if (sr->v[maxi2].first == sr->v[maxi2].second && h[sr->v[maxi2].first] > h[sl->v[maxi1].second])v[i].second = sl->v[maxi1].second;
                }
            }

        }
    }
    void rev() {
        if (l < r) {
            sl->rev();
            sr->rev();
        }
        reverse(vd.begin(), vd.end());
    }
    int query(int a, int b, int &rep, int dq) {
        if (a > r || b < l)return 0;
        if (a <= l && b >= r) {
            int i = lower_bound(vd.begin(), vd.end(), dq) - vd.begin();
            i = r - l + 1 - i;
            if (rep != -1) {
                int l1 = rep, r1 = v[i].first;
                if (t->qm(l1 + 1, r1 - 1) - dq >= max(h[l1], h[r1])) {
                    rep = v[i].second;
                    return i;
                }
                else {
                    if (v[i].first != v[i].second || h[v[i].first] < h[rep]) {
                        rep = v[i].second;
                    }
                    return i - 1;
                }
            }
            else {
                rep = v[i].second;
                return i;
            }
        }
        else {
            return sl->query(a, b, rep,dq) + sr->query(a, b, rep,dq);
        }
    }
};
node* seg;
void init(int N, std::vector<int> H) {
    for (int i = 0; i < N; i++)h[i] = H[i];
    seg = new node(0, N - 1);
    /*set<int> s;
    multiset<pi> d;
    for (int i = 0; i < N; i++)s.insert(i);
    for (int i = 0; i < N; i++)d.insert({ 0,i });
    while (s.size()>1) {
        auto it = d.begin(); pi p = *it;
        if(d.fi)
    }*/
    seg->calc(seg);
    seg->rev();
}
bool f = 0;
int max_towers(int L, int R, int D) {
    int k = -1;
    return seg->query(L, R, k,D);
}
/*
int main() {
    int N, Q;
    assert(2 == scanf("%d %d", &N, &Q));
    std::vector<int> H(N);
    for (int i = 0; i < N; ++i) {
        assert(1 == scanf("%d", &H[i]));
    }
    init(N, H);

    for (int i = 0; i < Q; ++i) {
        int L, R, D;
        assert(3 == scanf("%d %d %d", &L, &R, &D));
        printf("%d\n", max_towers(L, R, D));
    }
    return 0;
}*/

Compilation message (stderr)

towers.cpp:15: warning: ignoring '#pragma warning ' [-Wunknown-pragmas]
   15 | #pragma warning(disable : 4996)
      | 
towers.cpp: In member function 'void node::calc(node*)':
towers.cpp:52:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |             for (int i = 0; i < vec.size(); i++) {
      |                             ~~^~~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 11 / 11
• Subtask 3: 12 / 12
• Subtask 4: 14 / 14
• Subtask 5: 17 / 17
• Subtask 6: 19 / 19
• Subtask 7: 23 / 23