Submission #541769

#	Time	Username	Problem	Language	Result	Execution time	Memory
541769		AdamGS	Let's Win the Election (JOI22_ho_t3)	C++17	100 / 100	1650 ms	4408 KiB

Main

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
const int LIM=507;
const ld INF=1e9+7;
pair<int,int>T[LIM];
ld dp[LIM][LIM];
int n, k;
ld solve(int m) {
  rep(i, n+1) rep(j, k+1) dp[i][j]=INF;
  dp[0][0]=0;
  for(int i=1; i<=n; ++i) {
    for(int j=0; j<=i; ++j) {
      int l=min(i-j, m);
      if(j) {
        ld x=T[i-1].nd; x/=m+1;
        dp[i][j]=min(dp[i][j], dp[i-1][j-1]+x);
      }
      if(j<i) {
        ld x=T[i-1].st; x/=l;
        dp[i][j]=min(dp[i][j], dp[i-1][j]+x);
        if(i-j>m) {
          dp[i][j]=min(dp[i][j], dp[i-1][j]);
        }
      }
    }
  }
  return dp[n][k-m];
}
int main() {
  ios_base::sync_with_stdio(0); cin.tie(0);
  cin >> n >> k;
  rep(i, n) {
    cin >> T[i].nd >> T[i].st;
    if(T[i].st==-1) T[i].st=INF;
  }
  sort(T, T+n);
  ld ans=INF;
  rep(i, k+1) ans=min(ans, solve(i));
  cout << fixed << setprecision(3) << ans << '\n';
}

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