Submission #1157470

#	Time	Username	Problem	Language	Result	Execution time	Memory
1157470		vladilius	Let's Win the Election (JOI22_ho_t3)	C++20	100 / 100	1220 ms	5428 KiB

Main

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second
const ld inf = 1e9;

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    int n, k; cin>>n>>k;
    vector<pii> all(n + 1);
    for (int i = 1; i <= n; i++){
        cin>>all[i].ss>>all[i].ff;
        if (all[i].ff == -1) all[i].ff = inf;
    }
    
    sort(all.begin() + 1, all.end());
    
    vector<int> a(n + 1), b(n + 1);
    for (int i = 1; i <= n; i++){
        a[i] = all[i].ss;
        b[i] = all[i].ff;
    }
    
    vector<vector<int>> f(n + 2, vector<int>(k + 1, inf));
    multiset<int> st;
    for (int i = n + 1; i > 0; i--){
        if (i <= n) st.insert(a[i]);
        f[i][0] = 0;
        auto it = st.begin();
        for (int j = 1; j <= min((int) st.size(), k); j++){
            f[i][j] = f[i][j - 1] + (*it);
            it++;
        }
    }
    
    ld out = inf;
    for (int x = 0; x <= k; x++){
        vector<vector<ld>> dp(k + 1, vector<ld>(k + 1, inf)); dp[0][0] = 0;
        for (int i = 1; i <= k; i++){
            for (int j = 0; j <= i; j++){
                if (j) dp[i][j] = min(dp[i][j], dp[i - 1][j - 1] + 1.0 * a[i] / (x + 1));
                if (b[i] != -1 && j < i) dp[i][j] = min(dp[i][j], dp[i - 1][j] + 1.0 * b[i] / (i - j));
            }
        }
        
        for (int i = x; i <= k; i++){
            out = min(out, dp[i][i - x] + 1.0 * f[i + 1][k - i] / (x + 1));
        }
    }
    
    cout<<fixed<<setprecision(10)<<out<<"\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