Submission #754382

#	Time	Username	Problem	Language	Result	Execution time	Memory
754382		phongcd	Global Warming (CEOI18_glo)	C++14	100 / 100	146 ms	6328 KiB

glo

#include <bits/stdc++.h>
#define ll long long
#define ii pair <int, int>
#define ill pair <ll, ll>
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define file "test"
using namespace std;
const int N = 4e5 + 2;
const int MOD = 1e9 + 7;
const ll INF = 1e18;
const int base = 311;
const int BLOCK_SIZE = 2000;
 
int n, x;

struct tree {
    int bit[N] = {0};
    void upd(int idx, int v) {
        for (; idx <= 2 * n; idx += idx & -idx)
            bit[idx] = max(bit[idx], v);
    }

    int get(int idx) {
        int ans = 0;
        for (; idx > 0; idx -= idx & -idx)
            ans = max(ans, bit[idx]);
        return ans;
    }
} bit0, bit1;

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  
 
    cin >> n >> x;
    vector <int> a(n), b;
    for (int i = 0; i < n; i ++) {
        cin >> a[i];
        b.push_back(a[i]);
        b.push_back(a[i] + x);
    }

    sort(all(b));
    b.erase(unique(all(b)), b.end());
    for (int i = 0; i < n; i ++) {
        int ac = lower_bound(all(b), a[i] + x) - b.begin() + 1;
        a[i] = lower_bound(all(b), a[i]) - b.begin() + 1;
        
        int res = bit0.get(a[i] - 1) + 1;
        int res2 = max(bit0.get(ac - 1), bit1.get(a[i] - 1)) + 1;

        bit0.upd(a[i], res);
        bit1.upd(a[i], res2);
    }

    cout << bit1.get(2 * n);
} 
/*
     /\_/\ zzZ
    (= -_-)
    / >u  >u
*/

• 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