Submission #1154209

#	Time	Username	Problem	Language	Result	Execution time	Memory
1154209		mertbbm	Let's Win the Election (JOI22_ho_t3)	C++20	100 / 100	1154 ms	4216 KiB

Main

#include <bits/stdc++.h>
using namespace std;
 
#define int long long 
#define ld long double
#define show(x,y) cout << y << " " << #x << endl;
#define show2(x,y,i,j) cout << y << " " << #x << "  " << j << " " << #i << endl;
#define show3(x,y,i,j,p,q) cout << y << " " << #x << "  " << j << " " << #i << "  " << q << " " << #p << endl;
#define show4(x,y) for(auto it:y) cout << it << " "; cout << #x << endl;
typedef pair<int,int>pii;
typedef pair<pii,int>pi2;
mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());

pii arr[505];
int target=0;
int n,k;
bool visited[505][505];
ld memo[505][505];
int cnt=0;

ld dp(int index, int take){
	//cout << index << " " << take << "\n";
	if(index==n){
		//cout << take << " " << k << " " << index-take << " " << target << endl;
		if(k-take!=target) return 1e12;
		return 0.0;
	}
	if(visited[index][take]) return memo[index][take];
	ld ans=1e12;
	
	ans=min(ans,dp(index+1,take+1)+(ld)arr[index].second/(ld)(target+1));
	//cout << index-take << " " << target << endl;
	if(index-take<target) ans=min(ans,dp(index+1,take)+(ld)arr[index].first/(ld)(index-take+1)); //forced to do something
	else{
		//show(trigger,1);
		ans=min(ans,dp(index+1,take)); //do nothing
	}
	//cout << index << " " << take << ' ' << ans << endl;
	
	visited[index][take]=true;
	return memo[index][take]=ans;
}

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

	for(int x=0;x<n;x++){
		cin >> arr[x].second >> arr[x].first;
		if(arr[x].first==-1) arr[x].first=1e8;
		else cnt++;
	}
	
	sort(arr,arr+n);
	
	ld ans=1e15;
	for(int x=0;x<=min(cnt,k);x++){
		target=x;
		memset(visited,0,sizeof(visited));
		ans=min(ans,dp(0,0));
		//cout << ans << endl;
	}
	
	cout << fixed << setprecision(10) << ans << "\n";
}

int32_t main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	//freopen("in.txt","r",stdin);
	//freopen("in.txt","w",stdout);
	int t=1;	        
	//cin >> t;	
	while(t--){
		solve(); 
	}
}

• 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