Submission #915382

#	Time	Username	Problem	Language	Result	Execution time	Memory
915382		Pekiban	Split the sequence (APIO14_sequence)	C++17	22 / 100	303 ms	131072 KiB

sequence

#include <bits/stdc++.h>
 
using namespace std;
 
const int mxN = 1e5+2, mxK = 202;
long long pref[mxN], dp[mxK][mxN], to[mxK][mxN], c, t, h[mxN];
long double cord(int x, int y) {
    return (long double)(dp[c][y] - pref[y]*pref[y] + pref[x]*pref[x] - dp[c][x])/(pref[x] - pref[y]); // deljenje 0-om?
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n, k;
    cin >> n >> k;
    vector<int> z;
    for (int i = 1; i <= n; ++i) {
        int x;
        cin >> x;
        if (!x) {
            z.push_back(i);
            continue;
        }
        ++t;
        h[t] = i;
        pref[t] = pref[t-1] + x;
    }
    n = t;
    if (n == 1) {
        cout << 0 << '\n';
        for (int i = 1; i <= k; ++i) {
            cout << i << ' ';
        }
        return 0;
    }
    for (int i = 1; i <= k; ++i) {
        deque<int> dq = {0};
        for (int j = 1; j <= n; ++j) {
            while (dq.size() > 1 && cord(dq[0], dq[1]) <= pref[j])   dq.pop_front();
            dp[i][j] = pref[j]*pref[dq[0]] + dp[i-1][dq[0]] - pref[dq[0]]*pref[dq[0]];
            to[i][j] = dq[0];
            while (dq.size() > 1 && cord(dq[dq.size()-1], dq[dq.size()-2]) >= cord(dq[dq.size()-2], j)) dq.pop_back();
            dq.push_back(j);
        }
        ++c;
    }
    cout << dp[k][n] << '\n';
    vector<int> v = {n};
    int cnt = 0;
    for (int i = k; i >= 1; --i) {
        if (!to[i][v.back()]) {
            cnt = i;
            break;
        }
        v.push_back(to[i][v.back()]);
    }
    reverse(v.begin(), v.end()); v.pop_back();
    for (auto i : v) {
        cout << h[i] << '\n';
    }
}

Compilation message (stderr)

sequence.cpp: In function 'int main()':
sequence.cpp:49:9: warning: variable 'cnt' set but not used [-Wunused-but-set-variable]
   49 |     int cnt = 0;
      |         ^~~

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