Submission #579032

#	Time	Username	Problem	Language	Result	Execution time	Memory
579032		mousebeaver	Two Antennas (JOI19_antennas)	C++14	22 / 100	268 ms	14728 KiB

antennas

#define ll long long
#define ull unsigned ll
#define pii pair<int, int>
#define ppii pair<pii, int>
#include <bits/stdc++.h>
using namespace std;

int left(int i)
{
    return 2*i;
}

int right(int i)
{
    return 2*i+1;
}

int par(int i)
{
    return i/2;
}

ll query(vector<ll>& s, int a, int b, int l, int r, int i)
{
    //cout<<"HERE: "<<i<<" => <<endl;
    if(l <= a && b <= r)
    {
        //cout<<"END"<<endl;
        return s[i];
    }
    if(r < a || b < l)
    {
        //cout<<"END"<<endl;
        return numeric_limits<ll>::min();
    }
    int m = (a+b)/2;
    return max(query(s, a, m, l, r, left(i)), query(s, m+1, b, l, r, right(i)));
}

void propagate(vector<ll>& s, int i)
{
    s[i] = max(s[left(i)], s[right(i)]);
    if(i > 1)
    {
        propagate(s, par(i));
    }
}

void update(vector<ll>& s, int i, ll v)
{
    s[i+(s.size()/2)] = v;
    propagate(s, par(i+(s.size()/2)));
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin>>n;
    vector<ll> h(n); //heights
    vector<pii> a(n); //Bereiche
    for(int i = 0; i < n; i++)
    {
        cin>>h[i]>>a[i].first>>a[i].second;
    }

    int segnodes = 2*pow(2, ceil(log2(n)));
    //Segtrees for max:
    vector<ll> s(segnodes, numeric_limits<ll>::min()); //positive heights
    vector<ll> ns(segnodes, numeric_limits<ll>::min()); //negative heights

    int q;
    cin>>q;
    vector<ppii> requests(q);
    for(int i = 0; i < q; i++)
    {
        int l, r;
        cin>>l>>r;
        requests[i] = {{l, r}, i};
    }
    sort(requests.begin(), requests.end());
    vector<ll> result(q);
    int qindex = 0;

    while(qindex < q)
    {
        int l = requests[qindex].first.first;
        ll output = -1;
        priority_queue<pii, vector<pii>, greater<pii>> st; //starts: distance, index
        priority_queue<pii, vector<pii>, greater<pii>> g; //goals: distance, index
        st.push({a[l-1].first+l, l});
        g.push({a[l-1].second+l+1, l});
        //cout<<"___________________________________NEW QUERY!!!"<<endl;

        int j = l+1;
        while(qindex < n && requests[qindex].first.first == l)
        {
            int r = requests[qindex].first.second;
            //cout<<"-------->: "<<j<<endl;
            while(!st.empty() && st.top().first == j)
            {
                update(s, st.top().second-1, h[st.top().second-1]);
                update(ns, st.top().second-1, 0-h[st.top().second-1]);
                //cout<<"TAKE "<<st.top().second<<endl;
                st.pop();
            }
            while(!g.empty() && g.top().first == j)
            {
                update(s, g.top().second-1, numeric_limits<ll>::min());
                update(ns, g.top().second-1, numeric_limits<ll>::min());
                //cout<<"DROP "<<g.top().second<<endl;
                g.pop();
            }
            st.push({a[j-1].first+j, j});
            g.push({a[j-1].second+j+1, j});
            /*cout<<"SEGTREE S: "<<endl;
            for(ll y : s)
            {
                cout<<y<<" ";
            }
            cout<<endl;*/
            int left = max(j-a[j-1].second, l);
            int right = max(j-a[j-1].first, l);
            //cout<<"LEFT: "<<left<<", RIGHT: "<<right<<endl;
            ll biggest = query(s, 1, segnodes/2, left, right, 1);
            ll smallest = query(ns, 1, segnodes/2, left, right, 1);
            //cout<<"BIGGEST: "<<biggest<<", SMALLEST: "<<smallest<<endl;
            if(biggest > numeric_limits<ll>::min())
            {
                //cout<<"HEREBIG"<<endl;
                output = max(output, abs(h[j-1]-biggest));
            }
            if(smallest > numeric_limits<ll>::min())
            {
                //cout<<"HERESMALL"<<endl;
                output = max(output, abs(h[j-1]+smallest));
            }
            //cout<<"OUTPUT: "<<output<<endl;
            if(j == r)
            {
                while(qindex < q && requests[qindex].first.second == r)
                {
                    result[requests[qindex].second] = output;
                    qindex++;
                }
            }
            j++;
        }
        while(!g.empty())
        {
            update(s, g.top().second-1, numeric_limits<ll>::min());
            update(ns, g.top().second-1, numeric_limits<ll>::min());
            g.pop();
        }
    }

    for(ll i : result)
    {
        cout<<i<<"\n";
    }

    return 0;
}

• Subtask 1: 0 / 2
• Subtask 2: 0 / 11
• Subtask 3: 22 / 22
• Subtask 4: 0 / 65