Submission #1023209

#	Time	Username	Problem	Language	Result	Execution time	Memory
1023209		snpmrnhlol	Let's Win the Election (JOI22_ho_t3)	C++17	100 / 100	1597 ms	4444 KiB

Main

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
const ll N = 5e2;
const ll inf = 1e18;
struct state{
    ll a,b;
}v[N];
int p[N];
ld dp[N + 1][N + 1];
ll sum[N + 1];
vector<int> v2;
int main(){
    cout<<fixed<<setprecision(5);
    int n,k;
    ld ans = inf;
    cin>>n>>k;
    for(int i = 0;i < n;i++){
        cin>>v[i].a>>v[i].b;
        if(v[i].b == -1)v[i].b = inf;
        p[i] = i;
    }
    sort(p,p + n,[&](int a, int b){
         return v[a].b < v[b].b;
    });
    for(int i = n;i >= 0;i--){
        ///first i - 1 complete
        v2.clear();
        for(int j = i;j < n;j++){
            v2.push_back(v[p[j]].a);
        }
        sort(v2.begin(),v2.end());
        for(int j = 0;j < k - i;j++){
            sum[i]+=v2[j];
        }
    }
    for(int m = 0;m < k;m++){
        for(int i = 0;i <= n;i++){
            for(int j = 0;j <= n;j++){
                dp[i][j] = inf;
            }
        }
        dp[0][0] = 0;///i as j bs
        for(int i = 0;i <= n;i++){
            int id = p[i];
            for(int j = 0;j <= i;j++){
                if(i - j + 1 <= n)dp[i - j + 1][j] = min(dp[i - j + 1][j],dp[i - j][j] + (ld)v[id].a/(m + 1));
                if(j + 1 <= n)dp[i - j][j + 1] = min(dp[i - j][j + 1],dp[i - j][j] + (ld)v[id].b/(j + 1));
            }
        }
        for(int i = 0;i + m <= n;i++){
            ans = min(ans,dp[i][m] + (ld)sum[i + m]/(m + 1));
        }
    }
    cout<<ans;
    return 0;
}
/**
7 5
284 758  x 474
288 668    380
320 635    315
333 702  x 369
374 676    302
375 666 x  291
393 646 x  253
**/

• 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