Submission #1296180

#	Time	Username	Problem	Language	Result	Execution time	Memory
1296180		InvMOD	Two Antennas (JOI19_antennas)	C++17	100 / 100	554 ms	41660 KiB

antennas

#include<bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define pb push_back
#define eb emplace_back

#define vi vector<int>
#define pi pair<int,int>
#define sz(v) (int)(v).size()
#define all(v) (v).begin(), (v).end()
#define compact(v) (v).erase(unique(all(v)), (v).end())

template<class T> using upq = priority_queue<T, vector<T>, greater<T>>;
template<class T> int lwrbound(const vector<T>& a, const T& b, const int s = 0){return int(lower_bound(s + all(a), b) - a.begin());}
template<class T> int uprbound(const vector<T>& a, const T& b, const int s = 0){return int(upper_bound(s + all(a), b) - a.begin());}

#define FOR(i, a, b) for(int i = (a); i <= (b); i++)
#define ROF(i, a, b) for(int i = (a); i >= (b); i--)
#define sumof(x) accumulate(all(x), 0ll)
#define dbg(x) "[" << #x " = " << (x) << "]"
#define el "\n"

using ll = long long;
using ld = long double;

template<class T> bool ckmx(T& a, const T b){return (a < b ? a = b, true : false);}
template<class T> bool ckmn(T& a, const T b){return (a > b ? a = b, true : false);}

struct Node{
    int ans, Mx, trv;

    Node(int ans = -1e9, int Mx = -1e9, int trv = -1e9): ans(ans), Mx(Mx), trv(trv) {}

    Node operator + (const Node q) const{
        Node ret;
        ret.ans = max(ans, q.ans);
        ret.Mx = max(Mx, q.Mx);
        return ret;
    }
};

struct SMT{
    vector<Node> st; int trsz;

    SMT(int n = 0): st((n << 2) | 1), trsz(n) {}

    void apply(int id, int val){
        ckmx(st[id].ans, val + st[id].Mx);
        ckmx(st[id].trv, val);
    }

    void down(int id){
        if(st[id].trv != -1e9){
            apply(id << 1, st[id].trv);
            apply(id << 1|1, st[id].trv);
            st[id].trv = -1e9;
        }
    }

    void setNode(int id, int l, int r, int x, int v){
        if(l == r){
            if(v) st[id].Mx = v;
            else{
                st[id].Mx = -1e9;
            }
        }
        else{
            int m = l+r>>1; down(id);
            if(x <= m)
                setNode(id << 1, l, m, x, v);
            else setNode(id << 1|1, m+1, r, x, v);
            st[id] = st[id << 1] + st[id << 1|1];
        }
    }

    void setNode(int x, int v){
        setNode(1, 1, trsz, x, v);
    }

    void update(int id, int l, int r, int u, int v, int val){
        if(l >= u && r <= v){
            apply(id, val);
            return;
        }
        int m = l+r>>1; down(id);
        if(u <= m) update(id << 1, l, m, u, v, val);
        if(v > m) update(id << 1|1, m+1, r, u, v, val);
        st[id] = st[id << 1] + st[id << 1|1];
    }

    void update(int l, int r, int val){
        l = max(1, l);
        if(l > r) return;
        update(1, 1, trsz, l, r, val);
    }

    int get(int id, int l, int r, int u, int v){
        if(l > v || r < u) return -1e9;
        if(l >= u && r <= v) return st[id].ans;
        int m = l+r>>1; down(id);
        return max(get(id << 1, l, m, u, v), get(id << 1|1, m+1, r, u, v));
    }

    int query(int l, int r){
        return get(1, 1, trsz, l, r);
    }
};

void Main()
{
    int N; cin >> N;

    vi H(N + 1), A(N + 1), B(N + 1);
    FOR(i, 1, N){
        cin >> H[i] >> A[i] >> B[i];
    }

    int Q; cin >> Q;

    vector<pi> q(Q + 1); vector<vi> quer(N + 1);
    FOR(i, 1, Q){
        cin >> q[i].fi >> q[i].se;
        quer[q[i].se].eb(i);
    }

    vector<vector<pi>> op(N + 1);
    vi ans(Q + 1, -1); SMT st1(N), st2(N);

    FOR(i, 1, N){
        for(pi e : op[i]){
            int t = e.fi, w = e.se;
            if(t > 0){
                st1.setNode(w, -H[w]);
                st2.setNode(w, +H[w]);
            }
            else st1.setNode(w, 0), st2.setNode(w, 0);
        }

        int L = i - B[i];
        int R = i - A[i];
        st1.update(L, R, +H[i]);
        st2.update(L, R, -H[i]);

        for(int j : quer[i]){
            ans[j] = max(st1.query(q[j].fi, q[j].se), st2.query(q[j].fi, q[j].se));
        }

        if(i + A[i] <= N) op[i + A[i]].eb(+1, i);
        if(i + B[i] + 1 <= N) op[i + B[i] + 1].eb(-1, i);
    }

    FOR(i, 1, Q){
        cout << (ans[i] < 0 ? -1 : ans[i]) << el;
    }
}

int32_t main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    #define name "InvMOD"
    if(fopen(name".INP", "r")){
        freopen(name".INP", "r", stdin);
        freopen(name".OUT", "w", stdout);
    }

    int t = 1; while(t--) Main();
    return 0;
}

Compilation message (stderr)

antennas.cpp: In function 'int32_t main()':
antennas.cpp:167:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  167 |         freopen(name".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
antennas.cpp:168:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  168 |         freopen(name".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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