Submission #344886

#	Time	Username	Problem	Language	Result	Execution time	Memory
344886		spike1236	수열 (APIO14_sequence)	C++14	71 / 100	2095 ms	88940 KiB

sequence

#include <bits/stdc++.h>

const int MAXN = 1e5 + 10;
int64_t pref[MAXN];
int64_t dp[MAXN][2];
int opt[MAXN][220];
int n, K;

void calc(int k, int l, int r, int optl, int optr) {
    if(l > r) return;
    int m = l + r >> 1;
    int64_t res = -1e18;
    opt[m][k] = optl;
    for(int i = optl; i <= std::min(m - 1, optr); ++i) {
        int64_t cur = dp[i][(k & 1) ^ 1] + pref[i] * (pref[m] - pref[i]);
        if(cur > res) {
            res = cur;
            opt[m][k] = i;
        }
    }
    dp[m][k & 1] = res;
    calc(k, l, m - 1, optl, opt[m][k]);
    calc(k, m + 1, r, opt[m][k], optr);
}


void solve() {
    std::cin >> n >> K;
    for(int i = 1; i <= n; ++i) {
        int64_t x;
        std::cin >> x;
        pref[i] = pref[i - 1] + x;
    }
    for(int i = 1; i <= K; ++i)
        calc(i, i + 1, n, i, n);
    std::vector <int> ans;
    int pos = n;
    for(int i = K; i > 0; --i)
        pos = opt[pos][i], ans.push_back(pos);
    for(int i = 0; i < (ans.size() >> 1); ++i) {
        int k = ans[i];
        ans[i] = ans[(int)ans.size() - i - 1];
        ans[(int)ans.size() - i - 1] = k;
    }
    std::cout << dp[n][K & 1] << '\n';
    for(auto it : ans) std::cout << it << ' ';
}


int main() {
    std::ios_base::sync_with_stdio(0);
    std::cin.tie(0);
    std::cout.tie(0);
    solve();
    return 0;
}
/**
7 3
4 1 3 4 0 2 3
*/

Compilation message (stderr)

sequence.cpp: In function 'void calc(int, int, int, int, int)':
sequence.cpp:11:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   11 |     int m = l + r >> 1;
      |             ~~^~~
sequence.cpp: In function 'void solve()':
sequence.cpp:40:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |     for(int i = 0; i < (ans.size() >> 1); ++i) {
      |                    ~~^~~~~~~~~~~~~~~~~~~

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