Submission #1093045

#	Time	Username	Problem	Language	Result	Execution time	Memory
1093045		TommasoUlian	Mobile (BOI12_mobile)	C++17	0 / 100	1055 ms	56936 KiB

mobile

#include <bits/stdc++.h>
#define PB push_back
#define MP makepair
#ifndef ONLINE_JUDGE
#define DEBUG(x) cout << #x << " = " << (x) << endl
#else
#define DEBUG(x)
#endif
#define FOR(n) for(int i = 0; i < (n); i++)
#define SORTA(v) sort((v).begin(), (v).end())
#define SORTD(v) sort((v).rbegin(), (v).rend())
#define PRINT(v) for(auto x: (v))cout << x << " "; cout << endl;
#define TWO(n) (1 << (n))
#define INPUT(v) for(auto &x : (v))cin >> x;
#pragma GCC optimize("Ofast,no-stack-protector",3)
 
typedef long long ll;
 
using namespace std;
 
vector<pair<double,double>> torri;
ll n,L;
 
bool good(double r){
    priority_queue<pair<double,double>, vector<pair<double,double>>, greater<pair<double,double>>> s;
    
    for(auto a:torri){
        double x = a.first, y = a.second;
        if (abs(y) <= r - 1e-6)s.push({max(0.0,x-sqrt(r*r-y*y)),min((double)L,x+sqrt(r*r-y*y))});
    }
    double curr = 0;
    while(!s.empty()){
        if(curr >= L)return true;
        auto seg = s.top();
        s.pop();
        if(seg.first <= curr){
            curr = seg.second;
        }
        else return false;
    }
    if(curr < L)return false;
    return true;
}
 
void solve(){
    cin >> n >> L;
    torri = vector<pair<double,double>>(n);
    for(int i = 0; i < n; i++){
        cin >> torri[i].first >> torri[i].second;
 
    }
    double l = 1, r = 20e14;
    double ans = r;
    
    while(r-l >= 0.000001){
        double c = (r+l)/2;
        //cout << c << endl;
        if(good(c)){
            ans = min(ans,c);
            r = c;
        }
        else{
            l = c;
        }
 
    }
    cout << ans << endl;
    
}
 
int main(){
    cout << setprecision(18);
    ios::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);
    solve();
    return 0;
}

• Subtask 1: 0 / 4
• Subtask 2: 0 / 4
• Subtask 3: 0 / 4
• Subtask 4: 0 / 4
• Subtask 5: 0 / 4
• Subtask 6: 0 / 5
• Subtask 7: 0 / 5
• Subtask 8: 0 / 5
• Subtask 9: 0 / 5
• Subtask 10: 0 / 5
• Subtask 11: 0 / 5
• Subtask 12: 0 / 5
• Subtask 13: 0 / 5
• Subtask 14: 0 / 5
• Subtask 15: 0 / 5
• Subtask 16: 0 / 5
• Subtask 17: 0 / 5
• Subtask 18: 0 / 5
• Subtask 19: 0 / 5
• Subtask 20: 0 / 5
• Subtask 21: 0 / 5