Submission #106418

#	Time	Username	Problem	Language	Result	Execution time	Memory
106418		abil	Split the sequence (APIO14_sequence)	C++14	71 / 100	226 ms	132096 KiB

sequence

#include <bits/stdc++.h>
#define int long long
#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() )
#define Scan(a) scanf ("%I64d", &a)
#define scan(a) scanf ("%d", &a)
#define pi pair < long long, long long >

using namespace std;

const long long INF = (int)1e18 + 7;
const int N = (int)100007;
const int mod = 1000000007;

int n, k, arr[N], pr[N], par[N][207];
int dp[N][207];

int calc(int l,int r){
      return pr[l] * (pr[r] - pr[l]);
}
void solve(int k,int l,int r,int optl,int optr){
      if(l > r){
            return;
      }
      int mid = (l + r) >> 1;
      int opt = optl;
      dp[mid][k] = 0;
      for(int i = optl;i <= min(mid,optr); i++){
            int cur = dp[i][k - 1] + calc(i,mid);
            if(cur >= dp[mid][k]){
               dp[mid][k] = cur;
               opt = i;
            }
      }
      par[mid][k] = opt;
      solve(k,l,mid - 1,optl,opt);
      solve(k,mid + 1,r,opt,optr);
}
main(){
      cin >> n >> k;
      for(int i = 1;i <= n; i++){
            cin >> arr[i];
            pr[i] = pr[i - 1] + arr[i];
      }
      if(n < 10000){
            for(int g = 1;g <= k; g++){
                  for(int i = 1;i <= n; i++){
                        for(int j = 1;j < i; j++){
                              if(dp[i][g] <= dp[j][g - 1] + (pr[j] * (pr[i] - pr[j]))){
                                    par[i][g] = j;
                                    dp[i][g] = dp[j][g - 1] + (pr[j] * (pr[i] - pr[j]));
                              }

                        }
                  }
            }
            cout << dp[n][k] << endl;
            vector<int > ans;
            while(par[n][k]){
                  ans.pb(par[n][k]);
                  n = par[n][k];
                  k--;
            }
            for(int i = ans.size() - 1; i >= 0; i--){
                  cout << ans[i] << " ";
            }
            return 0;
      }
      for(int i = 1;i <= k; i++){
            solve(i,1,n,1,n);
      }
      cout << dp[n][k] << '\n';
      vector<int > ans;
      while(par[n][k]){
            ans.pb(par[n][k]);
            n = par[n][k];
            k--;
      }
      for(int i = ans.size() - 1; i >= 0; i--){
            cout << ans[i] << " ";
      }
}
/*
7 3
4 1 3 4 0 2 3
*/

Compilation message (stderr)

sequence.cpp:43:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main(){
      ^

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