Submission #1268763

#	Time	Username	Problem	Language	Result	Execution time	Memory
1268763		rafamiune	Global Warming (CEOI18_glo)	C++20	100 / 100	291 ms	20660 KiB

glo

#include <bits/stdc++.h>
using namespace std;
#define fr first
#define sc second
#define int long long
#define all(x) (x).begin(), (x).end()
const int MOD = 1e9 + 7;
const int MAXN = 2e5 + 5;
const long long INF = 1e18 + 5;

vector<int> tr(8*MAXN);

void update(int node, int l, int r, int pos, int val) {
    if(l == r) {
        tr[node] = val;
        return;
    }
    int mid = (l+r)/2, lc = 2*node + 1, rc = 2*node + 2;
    if(pos <= mid) update(lc, l, mid, pos, val);
    if(pos > mid) update(rc, mid + 1, r, pos, val);
    tr[node] = max(tr[lc],tr[rc]);
}

int query(int node, int l, int r, int ll, int rr) {
    if(l > rr || r < ll) return 0;
    if(l >= ll && r <= rr) return tr[node];
    int mid = (l+r)/2, lc = 2*node + 1, rc = 2*node + 2;
    return max(query(lc, l, mid, ll, rr),query(rc, mid + 1, r, ll, rr));
}

int32_t main() {
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    int n, x;
    cin >> n >> x;
    vector<int> v(n+1), vx(n+1), aux;
    for(int i = 1; i <= n; i++) {
        cin >> v[i];
        vx[i] = v[i] + x;
        aux.push_back(v[i]);
        aux.push_back(vx[i]);
    }   
    //compressão de coordenadas
    sort(all(aux));
    aux.erase(unique(all(aux)), aux.end());
    for(int i = 1; i <= n; i++) {
        v[i] = lower_bound(all(aux), v[i]) - aux.begin() + 1;
        vx[i] = lower_bound(all(aux), vx[i]) - aux.begin() + 1;
    }
    //valor da maior LIS acabando no i-ésimo cara
    vector<int> sz(n+1);
    sz[0] = 0;
    for(int i = 1; i <= n; i++) {
        int max_sz = query(0, 0, 2*n + 1, 1, v[i] - 1);
        sz[i] = max_sz + 1;
        update(0, 0, 2*n + 1, v[i], sz[i]);
    }
    //reiniciando a segment tree
    for(int i = 0; i < 8*MAXN; i++) tr[i] = 0;
    //calculando de trás pra frente
    int ans = sz[n];
    for(int i = n; i >= 1; i--) {
        int max_sz = query(0, 0, 2*n + 1, vx[i] + 1, 2*n + 1);
        update(0, 0, 2*n + 1, vx[i], max_sz + 1);
        ans = max(ans, sz[i-1] + query(0, 0, 2*n + 1, v[i-1] + 1, 2*n + 1));
    }

    cout << ans << "\n";

    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 13 / 13
• Subtask 4: 10 / 10
• Subtask 5: 20 / 20
• Subtask 6: 17 / 17
• Subtask 7: 25 / 25