Submission #1022487

#	Time	Username	Problem	Language	Result	Execution time	Memory
1022487		daffuwu	Split the sequence (APIO14_sequence)	C++14	71 / 100	644 ms	82008 KiB

sequence

#include <bits/stdc++.h>
using namespace std;
#define fr first
#define sc second
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

int n, k, opt[100002][202], ps[100069];
long long dp[100069][2];

void dnc(int l, int r, int c, int optl, int optr)
{
    if (l>r) return;
    int m = (l+r)/2, i;
    long long val;
    dp[m][c%2] = -1e15;
    for (i=optl; i<=min(m-1, optr); i++)
    {
        val = dp[i][(c+1)%2]+1ll*(ps[m]-ps[i])*ps[i];
        if (val>dp[m][c%2])
        {
            dp[m][c%2] = val;
            opt[m][c] = i;
        }
    }
    dnc(l, m-1, c, optl, opt[m][c]);
    dnc(m+1, r, c, opt[m][c], optr);
}

int main() 
{
    int i, j, c;
    scanf("%d%d", &n, &k);
    k++;
    for (i=1; i<=n; i++)
    {
        scanf("%d", ps+i);
        ps[i] += ps[i-1];
        dp[i][0] = -1e15;
    }
    for (c=1; c<=k; c++)
    {
        dp[0][c%2] = -1e15;
        dnc(1, n, c, 0, n-1);
    }
    printf("%lld\n", dp[n][k%2]);
    for (i=n, c=k; c>=2; i=opt[i][c], c--)
    {
        printf("%d ", opt[i][c]);
    }
    printf("\n");
}

Compilation message (stderr)

sequence.cpp: In function 'int main()':
sequence.cpp:31:12: warning: unused variable 'j' [-Wunused-variable]
   31 |     int i, j, c;
      |            ^
sequence.cpp:32:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     scanf("%d%d", &n, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~
sequence.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |         scanf("%d", ps+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