Submission #1278516

#	Time	Username	Problem	Language	Result	Execution time	Memory
1278516		lkateris	Mobile (BOI12_mobile)	C++20	100 / 100	266 ms	16940 KiB

mobile

#include <iostream>
#include <utility>
#include <vector>
#include <cmath>

using namespace std;

vector< pair<long long int,long long int> > A;

int main() {

    int N,L;
    scanf("%d %d",&N,&L);

    for(int i=0;i<N;++i) {
        int x,y;
        scanf("%d %d",&x,&y);
        A.push_back({x,y});
    }

    double l = 1;
    double r = 1.5e9;
    while (r-l > 1e-4) {
        double mid = (l+r)/2;

        double last = 0;
        for(int i=0;i<N;++i) {
            if ((double)abs(A[i].second) > mid) continue;
            double c = sqrt(mid*mid - A[i].second*A[i].second);
            double a = A[i].first - c,b = A[i].first + c;
            if (a <= last) last = max(last,b);
        }
        if (last >= L) r = mid;
        else l = mid;
    }

    printf("%lf",l);


    return 0;
}

Compilation message (stderr)

mobile.cpp: In function 'int main()':
mobile.cpp:13:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |     scanf("%d %d",&N,&L);
      |     ~~~~~^~~~~~~~~~~~~~~
mobile.cpp:17:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |         scanf("%d %d",&x,&y);
      |         ~~~~~^~~~~~~~~~~~~~~

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