제출 #238041

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
238041		DS007	수열 (APIO14_sequence)	C++14	60 / 100	125 ms	131076 KiB

sequence

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define evaluate(pt, x) (pt.first.first * x + pt.first.second)

const int N = 1e5, K = 205;
int a[N], s[N], p[K], n, k, dp[N][K], last[N][K];
vector<pair<pair<int, int>, int>> hull[K];

int find(int i, int j, int x) {
    p[j] = min(p[j], (int)hull[j].size() - 1);
    for (; p[j] < (int)hull[j].size() - 1; p[j]++) {
        if (evaluate(hull[j][p[j]], x) > evaluate(hull[j][p[j] + 1], x))
            break;
    }
    last[i][j + 1] = hull[j][p[j]].second;
    return evaluate(hull[j][p[j]], x);
}

bool inter(pair<int, int> a, pair<int, int> b, pair<int, int> c) {
    return (a.second - b.second) * (c.first - a.first) > (a.second - c.second) * (b.first - a.first);
}

void insert(int j, pair<pair<int, int>, int> nl) {
    while (hull[j].size() > 1) {
        auto temp = hull[j].back();
        hull[j].pop_back();

        if (inter(nl.first, temp.first, hull[j].back().first)) {
            hull[j].push_back(temp);
            break;
        }
    }
    hull[j].push_back(nl);
}

int solveTestCase() {
    cin >> n >> k;
    for (int i = 0; i < n; i++) cin >> a[i];

    s[0] = a[0];
    for (int i = 1; i < n; i++) s[i] = s[i - 1] + a[i];
    hull[0].push_back({{a[0], -a[0] * a[0]}, 0});

    for (int i = 1; i < n; i++) {
        for (int j = 1; j <= k && j <= i; j++) {
            dp[i][j] = find(i, j - 1, s[i]);
            insert(j - 1, {{s[i], dp[i][j - 1] - s[i] * s[i]}, i});
        }
        insert(min(i, k), {{s[i], dp[i][min(i, k)] - s[i] * s[i]}, i});
    }

    cout << dp[n - 1][k] << "\n";
    for (int i = last[n - 1][k], j = k; j > 0; --j, i = last[i][j]) cout << i + 1 << " ";
}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int test = 1;
    // cin >> test;
    while (test--)
        solveTestCase();
}

컴파일 시 표준 에러 (stderr) 메시지

sequence.cpp: In function 'long long int solveTestCase()':
sequence.cpp:55:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^

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