#include <bits/stdc++.h>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define int long long
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<double, double>;
const int mod = 1e9 + 7;
const int LOG = 20;
const int maxn = 1e5 + 5;
const double eps = 1e-9;
int32_t main() {
ios_base::sync_with_stdio(false);
cout.tie(0); cin.tie(0);
int n, L;
cin >> n >> L;
vector<int> x(n), y(n);
for(int i=0; i<n; i++) cin >> x[i] >> y[i];
double l=1, r=2e9, ans=r;
for(int it=0; it<50; it++) {
double mid = (l + r) / 2.0;
vector<pdd> seg;
for(int i=0; i<n; i++) {
if(abs(y[i]) >= mid) continue;
double len = sqrt(mid * mid - y[i] * y[i]);
double left = x[i] - len, right = x[i] + len;
if( right >= 0 && left <= L ) seg.push_back({ max((double)0, x[i] - len), min((double)L, x[i] + len) });
}
if(seg.size() == 0) {
l = mid;
continue;
}
//sort(seg.begin(), seg.end());
bool ok = 1;
double mn = 1e9;
for(auto &s : seg) mn = min(mn, s.first);
if(mn > 0) ok = 0;
double lp=seg[0].first, rp=seg[0].second;
for(int i=1; i<seg.size(); i++) {
if(seg[i].first <= rp) rp = max(rp, seg[i].second);
}
if(ok && rp >= L) ans = min(ans, mid), r = mid;
else l = mid;
}
cout << setprecision(8) << fixed << ans << '\n';
return 0;
}
Compilation message
mobile.cpp: In function 'int32_t main()':
mobile.cpp:57:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<double, double> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
57 | for(int i=1; i<seg.size(); i++) {
| ~^~~~~~~~~~~
mobile.cpp:55:16: warning: unused variable 'lp' [-Wunused-variable]
55 | double lp=seg[0].first, rp=seg[0].second;
| ^~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
1 ms |
344 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
1 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
604 KB |
Output is correct |
2 |
Correct |
2 ms |
612 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Correct |
1 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
748 KB |
Output is correct |
2 |
Correct |
5 ms |
748 KB |
Output is correct |
3 |
Correct |
4 ms |
748 KB |
Output is correct |
4 |
Correct |
3 ms |
748 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
732 KB |
Output is correct |
2 |
Correct |
5 ms |
748 KB |
Output is correct |
3 |
Correct |
4 ms |
748 KB |
Output is correct |
4 |
Correct |
3 ms |
748 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
748 KB |
Output is correct |
2 |
Correct |
5 ms |
748 KB |
Output is correct |
3 |
Correct |
4 ms |
748 KB |
Output is correct |
4 |
Correct |
4 ms |
732 KB |
Output is correct |
5 |
Correct |
3 ms |
748 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
51 ms |
4924 KB |
Output is correct |
2 |
Correct |
91 ms |
5800 KB |
Output is correct |
3 |
Correct |
63 ms |
3224 KB |
Output is correct |
4 |
Correct |
32 ms |
4900 KB |
Output is correct |
5 |
Correct |
32 ms |
3104 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
48 ms |
5024 KB |
Output is correct |
2 |
Correct |
38 ms |
4792 KB |
Output is correct |
3 |
Correct |
36 ms |
5932 KB |
Output is correct |
4 |
Correct |
33 ms |
5804 KB |
Output is correct |
5 |
Correct |
32 ms |
5228 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
96 ms |
5424 KB |
Output is correct |
2 |
Correct |
84 ms |
5956 KB |
Output is correct |
3 |
Correct |
56 ms |
5468 KB |
Output is correct |
4 |
Correct |
29 ms |
5564 KB |
Output is correct |
5 |
Correct |
49 ms |
5364 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
113 ms |
5808 KB |
Output is correct |
2 |
Correct |
106 ms |
5732 KB |
Output is correct |
3 |
Correct |
93 ms |
5724 KB |
Output is correct |
4 |
Correct |
31 ms |
5560 KB |
Output is correct |
5 |
Correct |
59 ms |
5692 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
50 ms |
5660 KB |
Output is correct |
2 |
Correct |
109 ms |
5752 KB |
Output is correct |
3 |
Correct |
100 ms |
5732 KB |
Output is correct |
4 |
Correct |
30 ms |
5560 KB |
Output is correct |
5 |
Correct |
49 ms |
5684 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
443 ms |
24604 KB |
Output is correct |
2 |
Correct |
486 ms |
32168 KB |
Output is correct |
3 |
Correct |
447 ms |
31580 KB |
Output is correct |
4 |
Correct |
144 ms |
33724 KB |
Output is correct |
5 |
Correct |
180 ms |
31548 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
489 ms |
24676 KB |
Output is correct |
2 |
Correct |
308 ms |
30964 KB |
Output is correct |
3 |
Correct |
397 ms |
30236 KB |
Output is correct |
4 |
Correct |
147 ms |
33592 KB |
Output is correct |
5 |
Correct |
181 ms |
31664 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
610 ms |
35932 KB |
Output is correct |
2 |
Correct |
640 ms |
46504 KB |
Output is correct |
3 |
Correct |
666 ms |
44964 KB |
Output is correct |
4 |
Correct |
176 ms |
48480 KB |
Output is correct |
5 |
Correct |
284 ms |
45448 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
678 ms |
36516 KB |
Output is correct |
2 |
Correct |
394 ms |
43680 KB |
Output is correct |
3 |
Correct |
398 ms |
43652 KB |
Output is correct |
4 |
Correct |
172 ms |
49320 KB |
Output is correct |
5 |
Correct |
247 ms |
45320 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
716 ms |
40412 KB |
Output is correct |
2 |
Correct |
679 ms |
50064 KB |
Output is correct |
3 |
Correct |
710 ms |
50268 KB |
Output is correct |
4 |
Correct |
211 ms |
54084 KB |
Output is correct |
5 |
Correct |
294 ms |
48112 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
713 ms |
40280 KB |
Output is correct |
2 |
Correct |
470 ms |
49584 KB |
Output is correct |
3 |
Correct |
479 ms |
47928 KB |
Output is correct |
4 |
Correct |
215 ms |
52400 KB |
Output is correct |
5 |
Correct |
275 ms |
49344 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
798 ms |
43204 KB |
Output is correct |
2 |
Correct |
833 ms |
54876 KB |
Output is correct |
3 |
Correct |
782 ms |
53740 KB |
Output is correct |
4 |
Correct |
234 ms |
58728 KB |
Output is correct |
5 |
Correct |
355 ms |
54496 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
805 ms |
41936 KB |
Output is correct |
2 |
Correct |
493 ms |
53340 KB |
Output is correct |
3 |
Correct |
678 ms |
52084 KB |
Output is correct |
4 |
Correct |
237 ms |
57632 KB |
Output is correct |
5 |
Correct |
355 ms |
54240 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
897 ms |
48212 KB |
Output is correct |
2 |
Correct |
923 ms |
63760 KB |
Output is correct |
3 |
Correct |
949 ms |
62936 KB |
Output is correct |
4 |
Correct |
292 ms |
68260 KB |
Output is correct |
5 |
Correct |
413 ms |
62464 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
981 ms |
48272 KB |
Output is correct |
2 |
Correct |
563 ms |
62216 KB |
Output is correct |
3 |
Correct |
804 ms |
60680 KB |
Output is correct |
4 |
Correct |
285 ms |
67904 KB |
Output is correct |
5 |
Correct |
376 ms |
62980 KB |
Output is correct |