Submission #1172004

#	Time	Username	Problem	Language	Result	Execution time	Memory
1172004		dmitryAdams	Feast (NOI19_feast)	C++20	100 / 100	434 ms	33252 KiB

feast

#include "bits/stdc++.h"
using namespace std;
# define int long long
# define all(a) a.begin(), a.end()
vector<int> a;
int n, k;
using int128_t = __int128_t;
const int128_t INF = 1e36;

vector<vector<pair<int128_t, int128_t>>> dp;
pair<int128_t, int128_t> check(int128_t x){
   dp.assign(n + 1, vector<pair<int128_t, int128_t>>(2, {-INF, 0}));
   dp[0][1] = {0, 0};
   for(int i = 1; i <= n; ++i){
      auto t1 = make_pair(dp[i - 1][0].first + a[i - 1], dp[i - 1][0].second);
      auto t2 = make_pair(dp[i - 1][1].first + x + a[i - 1], dp[i - 1][1].second - 1);
      dp[i][0] = max(t1, t2);
      dp[i][1] = max(dp[i - 1][0], dp[i - 1][1]);
   }
   return max(dp[n][0], dp[n][1]);
}
signed main(){
   ios::sync_with_stdio(false);
   cin.tie(nullptr);
   #ifdef LOCAL
   freopen("in.txt", "r", stdin);
   freopen("out.txt", "w", stdout);
   #endif
   cin >> n >> k;
   a.resize(n);
   for(auto &i : a) cin >> i;
   int128_t l = -1e18, r = 1;
   while(r - l > 1){
      int m = (r + l) / 2;
      if(-check(m).second >= k){
         r = m;
      } else {
         l = m;
      }
   }
   auto ans = check(r);
   ans.second = -ans.second;
   // cerr << (int)ans.second << '\n';
   cout << (int)(ans.first - r * ans.second) << '\n';
   return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 18 / 18
• Subtask 4: 10 / 10
• Subtask 5: 11 / 11
• Subtask 6: 20 / 20
• Subtask 7: 29 / 29