Submission #977218

#	Time	Username	Problem	Language	Result	Execution time	Memory
977218		LOLOLO	Global Warming (CEOI18_glo)	C++17	100 / 100	385 ms	8824 KiB

glo

#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
 
#define           f    first
#define           s    second
#define           pb    push_back
#define           ep    emplace
#define           eb    emplace_back
#define           lb    lower_bound
#define           ub    upper_bound
#define       all(x)    x.begin(), x.end()
#define      rall(x)    x.rbegin(), x.rend()
#define   uniquev(v)    sort(all(v)), (v).resize(unique(all(v)) - (v).begin())
#define     mem(f,x)    memset(f , x , sizeof(f))
#define        sz(x)    (int)(x).size()
#define  __lcm(a, b)    (1ll * ((a) / __gcd((a), (b))) * (b))
#define          mxx    *max_element
#define          mnn    *min_element
#define    cntbit(x)    __builtin_popcountll(x)
#define       len(x)    (int)(x.length())
 
const int N = 2e5 + 100;
struct st{
    vector <int> seg;
    void ass(int n) {
        seg.assign(n * 4 + 100, 0);
    }

    void upd(int id, int l, int r, int p, int v) {
        if (l > p || r < p)
            return;

        seg[id] = max(seg[id], v);
        if (l == r)
            return;

        int m = (l + r) / 2;
        upd(id * 2, l, m, p, v);
        upd(id * 2 + 1, m + 1, r, p, v);
        seg[id] = max(seg[id * 2], seg[id * 2 + 1]);
    }

    int get(int id, int l, int r, int u, int v) {
        if (l > v || r < u || u > v)
            return 0;

        int m = (l + r) / 2;
        if (l >= u && r <= v)
            return seg[id];

        return max(get(id * 2, l, m, u, v), get(id * 2 + 1, m + 1, r, u, v));
    }
};

int a[N];

vector <int> val;

int find(int x) {
    int p = lower_bound(all(val), x) - val.begin() + 1;
    return p;    
}

int pr[N], suff[N];

ll solve() {
    int n, x;
    cin >> n >> x;

    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        val.pb(a[i]);
    }

    uniquev(val);

    st seg;
    seg.ass(n);

    for (int i = 1; i <= n; i++) {
        int p = find(a[i]);
        pr[i] = seg.get(1, 1, n, 1, p - 1) + 1;
        seg.upd(1, 1, n, p, pr[i]);
    }


    seg.ass(n);

    for (int i = n; i >= 1; i--) {
        int p = find(a[i]);
        suff[i] = seg.get(1, 1, n, p + 1, n) + 1;
        seg.upd(1, 1, n, p, suff[i]);
    }

    int ans = 0;
    for (int i = 1; i <= n; i++)
        ans = max(ans, pr[i]);

    seg.ass(n);

    for (int i = 1; i < n; i++) {
        int p = find(a[i]);
        seg.upd(1, 1, n, p, pr[i]);
        int nxt = find(a[i + 1] + x - 1);
        ans = max(ans, seg.get(1, 1, n, 1, nxt - 1) + suff[i + 1]);
    }

    seg.ass(n);

    for (int i = n; i > 1; i--) {
        int p = find(a[i]);
        seg.upd(1, 1, n, p, suff[i]);
        int nxt = find(a[i - 1] - x + 1);
        ans = max(ans, seg.get(1, 1, n, nxt, n) + pr[i - 1]);
    }

    return ans;
}
 
int main(){
    ios_base::sync_with_stdio(false); 
    cin.tie(NULL);
    cout.tie(NULL);
 
    int t = 1;
    //cin >> t;
 
    while (t--) {
        //solve();
        cout << solve() << '\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