제출 #553428

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
553428		Hona_Nguyen	Mobile (BOI12_mobile)	C++14	100 / 100	887 ms	35404 KiB

mobile

#include<bits/stdc++.h>
#define prob "mobile"
#define x first
#define y second
using namespace std;
const int maxn = 1e6;
const int MOD = 1e9 + 7;
const double eps = 1e-9;
int n,L;
pair<double,double> p[maxn+5];
int main(){
//    freopen(prob".in","r",stdin);
//    freopen(prob".out","w",stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    cin >> n >> L;
    for(int i=1;i<=n;i++) cin >> p[i].x >> p[i].y;
    auto check = [&](double val) -> int{
//        vector<pair<double,double>> G;
        double curx = 0;
        for(int i=1;i<=n;i++){
//            if(val < p[i].y) return 0;
            double tmp = sqrt(val*val-p[i].y*p[i].y);
            double xL = p[i].x - tmp;
            double xR = p[i].x + tmp;
            if(xL <= curx){
                curx = max(curx, xR);
            }
//            G.push_back(make_pair(xL,xR));
        }
//        sort(G.begin(),G.end(), [](const pair<double,double> A, const pair<double,double> B){
//             if(A.first == B.first) return A.second < B.second;
//             return A.first < B.first;
//             });

//        for(int i=0;i<n;i++){
//            if(G[i].x <= curx){
//               curx = max(curx, G[i].y);
//            }
//        }
        if(curx >= (double)(L)) return 1;
        return 0;
    };
    double low = 1, high = (double)(1.5e9), res = 0;
    for(int i=1;i<=100;i++){
        if(high - low < eps) break;
        double mid = (low + high) / (double)(2);
        if(check(mid)){
            res = mid;
            high = mid;
        }
        else{
            low = mid;
        }
    }
    cout << fixed << setprecision(6);
    cout << res;
}

• 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