제출 #969384

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
969384		vjudge1	Cities (BOI16_cities)	C++17	0 / 100	21 ms	5480 KiB

cities

#include<bits/stdc++.h>
using namespace std;

#define pii pair<int,int>

const int mxN = 2e5+5;
int n, x, arr[mxN];
pii lis[mxN], inlis[mxN];
int last[mxN];

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> x;
    vector<int> temp;
    for(int i = 1; i <= n; ++i) {
        cin >> arr[i];
        auto itr = lower_bound(temp.begin(), temp.end(), arr[i]);
        if(itr == temp.end())
            temp.emplace_back(arr[i]);
        else
            *itr = arr[i];
        lis[i] = {temp[temp.size()-1], temp.size()};
    }
    temp.clear();
    for(int i = n; i >= 1; --i) {
        auto itr = lower_bound(temp.begin(), temp.end(), -arr[i]);
        if(itr == temp.end())
            temp.emplace_back(-arr[i]);
        else 
            *itr = -arr[i];

        inlis[i] = {-temp[temp.size()-1], temp.size()};
        // cout << inlis[i].first << ' ' << inlis[i].second << '\n';
    }

    // int ans = 0;
    int ans = lis[n].second;
    for(int i = 1; i < n; ++i) {
        pii t = {lis[i].first - x + 1, 0};
        int j = lower_bound(inlis+i+1, inlis+n, t) - inlis;
        int sum = lis[i].second + inlis[j].second;
        if(t.first > inlis[j].first) continue;
        if(sum > ans) {
            ans = sum;
            // cout << i << ' ' << j << '\n';
            // cout << t.first << ' ';
        }

    }
    cout << ans;

}

/*
8 7
7 3 5 12 -2 7 3 4

4 1
-9 -8 -7 -10
*/

• Subtask 1: 0 / 22
• Subtask 2: 0 / 14
• Subtask 3: 0 / 15
• Subtask 4: 0 / 23
• Subtask 5: 0 / 26