Submission #319924

#	Time	Username	Problem	Language	Result	Execution time	Memory
319924		tushar_2658	Split the sequence (APIO14_sequence)	C++14	0 / 100	69 ms	82660 KiB

sequence

#include "bits/stdc++.h"
using namespace std;

const int maxn = 100005;
using ll = long long;

ll dp[maxn][2];
int n, k;
ll a[maxn], pref[maxn];
int best[maxn][202];
int cur, cnt;

void compute(int l, int r, int optl, int optr){
  if(l > r)return;
  int mid = (l + r) >> 1;
  if(optl == optr){
    for(int i = l; i <= r; ++i){
      dp[i][cur] = dp[optl][cur ^ 1] + pref[optl] * (pref[mid] - pref[optl]);
      best[mid][cnt] = optl;
    }
    return;
  }
  int opt = optl;
  for(int i = optl; i <= min(mid - 1, optr); ++i){
    ll cost = dp[i][cur ^ 1] + pref[i] * (pref[mid] - pref[i]);
    if(dp[mid][cur] < cost){
      dp[mid][cur] = cost;
      opt = i;
    }
  }
  best[mid][cnt] = opt;
  compute(l, mid - 1, optl, opt);
  compute(mid + 1, r, opt, optr);
}

int main(int argc, char const *argv[])
{
  scanf("%d %d", &n, &k);
  for(int i = 1; i <= n; ++i){
    scanf("%lld", &a[i]);
    pref[i] = pref[i - 1] + a[i];
  }
  for(int i = 1; i <= k; ++i){
    cur = i & 1;
    cnt = i;
    for(int j = 0; j <= n; ++j){
      dp[j][cur] = -1;
    }
    compute(1, n, 1, n);
  }
  printf("%lld\n", dp[n][k & 1]);
  cur = n;
  int cur_k = k;
  while(cur_k > 0){
    printf("%d ", best[cur][cur_k]);
    cur = best[cur][cur_k];
    --cur_k;
  }

  return 0;
}

Compilation message (stderr)

sequence.cpp: In function 'int main(int, const char**)':
sequence.cpp:38:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   38 |   scanf("%d %d", &n, &k);
      |   ~~~~~^~~~~~~~~~~~~~~~~
sequence.cpp:40:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   40 |     scanf("%lld", &a[i]);
      |     ~~~~~^~~~~~~~~~~~~~~

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