Submission #873818

#	Time	Username	Problem	Language	Result	Execution time	Memory
873818		MisterReaper	Global Warming (CEOI18_glo)	C++17	100 / 100	50 ms	3812 KiB

glo

#include <bits/stdc++.h>
using namespace std;
using i64 = long long;

const int INF = 2E9;

ostream& operator<< (ostream& out, vector <int> dp) {
    out << "{";
    for(int i = 0; i < int(dp.size()); i++) {
        out << (abs(dp[i]) == INF ? -23 : dp[i]);
        if(i +1 != int(dp.size()))
            out << ", ";
    }

    return out << "}";
}

#define ONLINE_JUDGE
void solve() {
    int n, x;
    cin >> n >> x;

    vector <int> t(n +1);
    for(int i = 1; i <= n; i++)
        cin >> t[i];

    vector <int> dp(n +1, INF), left(n +1);
    for(int i = 1; i <= n; i++) {
        int idx = lower_bound(dp.begin(), dp.end(), t[i]) - dp.begin();
        dp[idx] = t[i];
        left[i] = idx +1;
    }

    dp = vector <int> (n +1, -INF);

    int ans = 0;
    for(int i = n; i >= 1; i--) {
        int idx = lower_bound(dp.begin(), dp.end(), t[i] - x, greater <int> ()) - dp.begin();
        //cerr << i << " || " << t[i] - x << " :: " << left[i] << " " << idx << " -> " << dp << "\n";
        ans = max(ans, left[i] + idx);
        idx = lower_bound(dp.begin(), dp.end(), t[i], greater <int> ()) - dp.begin();
        dp[idx] = t[i];
    }

    cout << ans;
    
    return;
}

signed main() {
    #ifndef ONLINE_JUDGE
        freopen(".in", "r", stdin);
        freopen(".out", "w", stdout);
    #endif

    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);

    int t = 1; //cin >> t;
    for(int i = 1; i <= t; i++) {
        solve();
    }

    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