Submission #476705

#	Time	Username	Problem	Language	Result	Execution time	Memory
476705		Shin	Split the sequence (APIO14_sequence)	C++14	100 / 100	1280 ms	80496 KiB

sequence

#include <bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define TASK ""
#define all(x) x.begin(), x.end()
 
using namespace std;
const int N = 1e5 + 7;
const int MOD = 1e9 + 7; // 998244353;
const int INF = 1e9 + 7;
const long long INFLL = 1e18 + 7;
 
typedef long long ll;
template <class X, class Y> bool minimize(X &a, Y b) {
    if (a > b) return a = b, true;
    return false;
}
template <class X, class Y> bool maximize(X &a, Y b) {
    if (a < b) return a = b, true;
    return false;
}
int n, k;
int pre[N];
ll dp[2][N];
int trace[222][N];
 
void compute(int l, int r, int li, int ri, int level) {
    if (l > r) return;
 
    int mid = (l + r) >> 1;
 
    pair<ll, int> best(-INF, 0);
    for (int i = li; i < min(mid, ri + 1); i ++) {
        ll tmp = 1LL * (pre[mid] - pre[i]) * (pre[n] - pre[mid]);
        maximize(best, mp(tmp + dp[!(level & 1)][i], i));
    }
 
    dp[level & 1][mid] = best.fi;
    trace[level][mid] = best.se;

    compute(l, mid - 1, li, best.se, level);
    compute(mid + 1, r, best.se, ri, level);
}
 
void solve(void) {
    cin >> n >> k;
    for (int i = 1; i <= n; i ++) {
        int x; cin >> x;
        pre[i] = pre[i - 1] + x;
    }
 
    for (int i = 1; i <= k; i ++) {
        compute(i, n - 1, 0, n - 1, i);
        // for (int j = 1; j <= n; j ++) cout << dp[i & 1][j] << ' ';
        // cout << '\n';
    }
 
    pair<ll, int> res(-INF, 0);
    for (int i = 1; i < n; i ++) maximize(res, mp(dp[k & 1][i], i));
    cout << res.fi << '\n';
    for (int cur = res.se; k; cur = trace[k][cur], k --)
        cout << cur << " ";
}
 
int main(void) {
    cin.tie(0)->sync_with_stdio(0); 
    int test = 1;
    // cin >> test;
    while (test --) {
        solve();
    }
    return 0;
}

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