Submission #973588

#	Time	Username	Problem	Language	Result	Execution time	Memory
973588		berr	Sandcastle 2 (JOI22_ho_t5)	C++17	0 / 100	1 ms	504 KiB

Main

#include <bits/stdc++.h>
using namespace std;
const int N = 505;

array<float, 2> dp[N][N];
 
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    
    int n, k; cin >> n >> k;
    vector<array<int, 2>> a(n);

    for(auto &[i, l]: a) cin >> i >> l;

    sort(a.begin(), a.end(), [&](auto x, auto y){
        if(x[1]==y[1]) return x[0] < y[0];
        else if(y[1]==-1) return true;
        else if(x[1]==-1) return false;
         return x[1]<y[1]; 
    });
    

    for(int i=0; i<=n+1; i++){
        for(int l=0; l<=n+1; l++){
            dp[i][l]={1e9, 1e9};
        }
    }

    dp[0][0]={0, 0};

    for(int i=0; i<n; i++){

        for(int l=n; l>=0; l--){
            for(int x=n; x>=0; x--){
              //  cout<<(float)a[i][1]/(float)(l+1)<<"\n";
                if(a[i][1]!=-1)
                dp[l+1][x]=min(dp[l+1][x], {dp[l][x][0]+(float)a[i][1]/(float)(l+1), dp[l][x][1]});
          
                dp[l][x+1]=min(dp[l][x+1], {dp[l][x][0], dp[l][x][1]+a[i][0]});

            }
        }

    }
    float ans=1e9;
    for(int i=0; i<=k; i++){

        ans=min(ans, dp[i][k-i][0]+(float)dp[i][k-i][1]/(float)(i+1));
    }

    cout<<setprecision(9)<<fixed<<ans<<"\n";
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 10
• Subtask 3: 0 / 5
• Subtask 4: 0 / 56
• Subtask 5: 0 / 20