Submission #197315

#	Time	Username	Problem	Language	Result	Execution time	Memory
197315		quocnguyen1012	Split the sequence (APIO14_sequence)	C++14	0 / 100	100 ms	80888 KiB

sequence

#include <bits/stdc++.h>

#define fi first
#define se second
#define mp make_pair
#define pb push_back

using namespace std;
typedef long long ll;

const int maxn = 1e5 + 5;

ll f[2][maxn];
int opt[201][maxn];
int N, K;
ll a[maxn];

bool Max(ll & a, ll b)
{
  if (a < b){
    a = b;
    return true;
  }
  return false;
}

void calc(int lev, int mid, int L, int R)
{
  f[1][mid] = -1e18;
  for (int i = L; i <= min(mid - 1, R); ++i){
    ///cerr << a[i] * (a[mid] - a[i]) << '\n';
    if (Max(f[1][mid], f[0][i] + a[i] * (a[mid] - a[i]))){
      opt[lev][mid] = i;
    }
  }
}

void solve(int lev, int l, int r, int L, int R)
{
  if (l > r) return;
  int mid = (l + r) / 2;
  calc(lev, mid, L, R);
  solve(lev, l, mid - 1, L, opt[lev][mid]);
  solve(lev, mid + 1, r, opt[lev][mid], R);
}

signed main(void)
{
  ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  if (fopen("A.INP", "r")){
    freopen("A.INP", "r", stdin);
    freopen("A.OUT", "w", stdout);
  }
  cin >> N >> K;
  for (int i = 1; i <= N; ++i){
    cin >> a[i];
    a[i] += a[i - 1];
  }
  for (int i = 1; i <= K; ++i){
    solve(i, 1, N, 0, N - 1);
    for (int j = 0; j <= N; ++j){
      f[0][j] = f[1][j];
    }
  }
  fill_n(&opt[0][0], 200 * maxn, 1);
  cout << f[1][N] << '\n';
  int n = N;
  for (int i = K; i >= 1; --i){
    cout << opt[i][n] << ' ';
    n = opt[i][n];
  }
}

Compilation message (stderr)

sequence.cpp: In function 'int main()':
sequence.cpp:51:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen("A.INP", "r", stdin);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
sequence.cpp:52:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen("A.OUT", "w", stdout);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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