Submission #734936

#	Time	Username	Problem	Language	Result	Execution time	Memory
734936		Sam_a17	Let's Win the Election (JOI22_ho_t3)	C++17	33 / 100	776 ms	372 KiB

Main

#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include "temp.cpp"
#include <cstdio>
using namespace std;
 
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
 
#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
#define blt(x) __builtin_popcount(x)
 
#define pb push_back
#define popf pop_front
#define popb pop_back
 
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
 
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(T v[],V n) {cerr << "["; for(int i = 0; i < n; i++) {print(v[i]); cerr << " "; } cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(deque <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
 
// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
 
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
  fastIO();
 
  if (str != "") {
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
  }
}
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const long double inf = 1e15;
int n, k;

void solve_() {
  cin >> n >> k;

  vector<pair<long double, long double>> vec;
  for(int i = 1; i <= n; i++) {
    long double a, b; cin >> a >> b;
    vec.emplace_back(b, a);
  }

  sort(all(vec));

  if(n <= 20) {
    long double pi = inf;

    for(int mask = 0; mask < (1 << n); mask++) {
      vector<long double> m1, m2;

      int ok = 1;
      for(int i = 0; i < n; i++) {
        if(mask & (1 << i)) {
          if(vec[i].first == -1) ok = 0;
          m1.push_back(vec[i].first);
        } else {
          m2.push_back(vec[i].second);
        }
      }

      if(!ok) continue;

      sort(all(m1));
      long double c1 = 1, ans = 0, it = 0;
      for(int i = 0; i < sz(m1); i++) {
        ans += m1[i] / c1;
        c1++, it++;

        if(it == k) {
          break;
        }
      }

      if(it < k) {
        sort(all(m2));
        for(int i = 0; i < sz(m2); i++) {    
          ans += m2[i] / c1;
          it++;

          if(it == k) {
            break;
          }
        }
      }

      pi = min(pi, ans);
    }

    cout << setprecision(15) << pi << '\n';
    return;
  }

  long double p = inf;
  for(int i = 0; i <= n; i++) {
    long double cnt = 1, ans = 0;
    vector<long double> vi;

    int cc = 0;
    for(int j = 0; j < i; j++) {
      if(vec[j].first == -1) {
        vi.push_back(vec[j].second);
        continue;
      }
      cc++;
      ans += vec[j].first / cnt;
      cnt += 1;
    }

    for(int j = i; j < n; j++) {
      vi.push_back(vec[j].second);
    }
    sort(all(vi));

    int it = 0, mm = k - cc;
    while(mm > 0) {
      ans += vi[it] / cnt; 
      it++, mm--;
    }

    p = min(p, ans);
  }

  cout << setprecision(15) << p << '\n';
}
 
int main() {
  setIO();
 
  auto solve = [&](int test_case)-> void {
    while(test_case--) {
      solve_();
    }
  };
 
  int test_cases = 1;
  // cin >> test_cases;
  solve(test_cases);
 
  return 0;
} 

Compilation message (stderr)

Main.cpp: In function 'void setIO(std::string)':
Main.cpp:64:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:65:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 0 / 33
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23