Submission #1233159

#	Time	Username	Problem	Language	Result	Execution time	Memory
1233159		fermat	Split the sequence (APIO14_sequence)	C++20	100 / 100	713 ms	81296 KiB

sequence

#include <iostream>
#include <vector>
#include <deque>
#include <math.h>
#include <set>
#include <iomanip>
#include <time.h>
#include <list>
#include <stdio.h>
#include <queue>
#include <map>
#include <algorithm>
#include <assert.h>
#include <memory.h>

#define mk make_pair
#define sc second
#define fr first
#define pb emplace_back
#define all(s) s.begin(), s.end()
#define sz(s) ( (int)s.size() )

using namespace std;

const int N = 1e5 + 5;

int n, p[205][N];

long long dp[45][N], pref[N], inf = 4e18;

void compute (int k, int l, int r, int opl, int opr)
{
    if (l > r) return;

    int md = (l + r) >> 1;

    int &opt = p[k][md];

    opt = opl;

    for (int i = opl; i <= min(opr, md - 1); i++)
    {
        if (dp[ (k & 1) ^ 1][i] + (pref[md] - pref[i]) * (pref[n] - pref[md]) >= dp[k & 1][md])
        {
            dp[k & 1][md] = dp[ (k & 1) ^ 1][i] + (pref[md] - pref[i]) * (pref[n] - pref[md]);
            opt = i;
        }
    }
    compute( k, l, md - 1, opl, opt );
    compute( k, md + 1, r, opt, opr );
}

int k;

main ()
{
    cin >> n >> k;

    for (int i = 0; i <= 1; i++)
        for (int j = 0; j <= n; j++)
            dp[i][j] = -inf;

    k++;

    for (int i = 1; i <= n; i++)
        scanf("%lld", &pref[i]),
        pref[i] += pref[i - 1];

    dp[0][0] = 0;

    for (int i = 1; i <= k; i++)
        compute( i, i, n, i - 1, n - 1 );

    cout << dp[k & 1][n] << endl;

    while (k > 1)
    {
        printf("%d ", p[k][n]);
        n = p[k][n];
        k--;
    }
}

Compilation message (stderr)

sequence.cpp:55:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   55 | main ()
      | ^~~~
sequence.cpp: In function 'int main()':
sequence.cpp:66:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   66 |         scanf("%lld", &pref[i]),
      |         ~~~~~^~~~~~~~~~~~~~~~~~

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