Submission #1167241

#	Time	Username	Problem	Language	Result	Execution time	Memory
1167241		mertbbm	Mobile (BOI12_mobile)	C++20	100 / 100	810 ms	31768 KiB

mobile

#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<int,pii>pi2;
mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());

void solve(){
	int n,k;
	cin >> n >> k;
	
	pair<ld,ld>arr[n];
	for(int x=0;x<n;x++){
		cin >> arr[x].first >> arr[x].second;
		if(arr[x].second<0) arr[x].second=-arr[x].second;
	}
	
	ld l=0.0;
	ld r=3e9;
	ld mid;
	ld best=r;
	
	int cnt=100;
	while(cnt--){
		mid=(l+r)/2.0;
	
		ld cur=0.0;
		for(int x=0;x<n;x++){
			if(arr[x].second>mid) continue;
			ld hold=sqrt(mid*mid-arr[x].second*arr[x].second);
			if(arr[x].first-hold<=cur){
				cur=max(cur,arr[x].first+hold);
			}
		}
		//show2(l,l,r,r);
		//show(cur,cur);
		
		if(cur>=(ld)k){
			best=mid;
			r=mid;
		}
		else l=mid;
	}
	
	cout << fixed << setprecision(10) << best;
}

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: 4 / 4
• Subtask 2: 4 / 4
• Subtask 3: 4 / 4
• Subtask 4: 4 / 4
• Subtask 5: 4 / 4
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 5 / 5
• Subtask 10: 5 / 5
• Subtask 11: 5 / 5
• Subtask 12: 5 / 5
• Subtask 13: 5 / 5
• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
• Subtask 18: 5 / 5
• Subtask 19: 5 / 5
• Subtask 20: 5 / 5
• Subtask 21: 5 / 5