제출 #396114

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
396114		talant117408	수열 (APIO14_sequence)	C++17	0 / 100	356 ms	17320 KiB

sequence

/*
    Code written by Talant I.D.
*/
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
 
using namespace __gnu_pbds;
using namespace std;
 
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
typedef tree <pii, null_type, less <pii>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
 
#define precision(n) fixed << setprecision(n)
#define pb push_back
#define ub upper_bound
#define lb lower_bound
#define mp make_pair
#define eps (double)1e-9
#define PI 2*acos(0.0)
#define endl "\n"
#define sz(v) int((v).size())
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define do_not_disturb ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define OK cout << "OK" << endl;
 
const int mod = 1e9+7;
 
ll mode(ll a) {
    a -= mod;
    if (a < 0) a += mod;
    return a;
}
 
ll subt(ll a, ll b) {
    return mode(mode(a)-mode(b));
}
 
ll add(ll a, ll b) {
    return mode(mode(a)+mode(b));
}
 
ll mult(ll a, ll b) {
    return mode(mode(a)*mode(b));
}
 
ll binpow(ll a, ll b) {
    ll res = 1;
    while (b) {
        if (b&1) res = mult(res, a);
        a = mult(a, a);
        b >>= 1;
    }
    return res;
}

const int N = 1e5+7;
ll dp[2][N], a[N], pref[N], par[203][N];

struct line {
    ll m, c;
    line(ll _m, ll _c) {
        m = _m; 
        c = _c;
    }
    ll get(ll x) {
        return m * x + c;
    }
    ll intersect(line other) {
        return (c - other.c) / (other.m - m);
    }
};

int main() {
    //~ do_not_disturb
    
    int n, K;
    cin >> n >> K;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        pref[i] = pref[i-1] + a[i];
    }
    
    for (int i = 1; i <= n; i++) {
        dp[1][i] = pref[i]*(pref[n]-pref[i]);
    }
    
    for (int k = 2; k <= K; k++) {
        int type = k&1;
        deque <pair <int, line>> K;
        vector <int> inds(n);
        iota(all(inds), 0);
        auto cmp = [&K](int i, ll x) {
            return K[i].second.intersect(K[i + 1].second) < x;  
        };
        K.push_front(mp(k-1, line(-pref[k-1], dp[1-type][k-1])));
        for (int i = k; i < n; i++) {
            int it = *lb(inds.begin(), inds.begin()+sz(K)-1, pref[n]-pref[i], cmp);
            ll res = 0ll+K[it].second.get(pref[n]-pref[i])+1ll*pref[i]*(pref[n]-pref[i]);
            dp[type][i] = res;
            par[k][i] = K[it].first;
            line cur = line(-pref[i], dp[1-type][i]);
            while (sz(K) >= 2 && ((cur.m == K[0].second.m && cur.c == K[0].second.c) || cur.intersect(K[0].second) >= K[0].second.intersect(K[1].second))) {
                K.pop_front();
            }
            K.push_front(mp(i, cur));
        }
    }
    
    int mx = -1, ind = 0;
    for (int i = 1; i <= n; i++) {
        if (dp[K&1][i] > mx) {
            mx = dp[K&1][i];
            ind = i;
        }
    }
    
    cout << mx << endl;
    vector <int> v;
    while (ind) {
        v.pb(ind);
        ind = par[K][ind];
        K--;
    }
    reverse(all(v));
    for (auto to : v) cout << to << ' ';
    
    return 0;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 11
• Subtask 3: 0 / 11
• Subtask 4: 0 / 17
• Subtask 5: 0 / 21
• Subtask 6: 0 / 29