Submission #656270

# Submission time Handle Problem Language Result Execution time Memory
656270 2022-11-06T16:48:25 Z chjiao Mobile (BOI12_mobile) C++14
0 / 100
369 ms 28568 KB
#include <bits/stdc++.h>
using namespace std;

#define fastio	ios_base::sync_with_stdio(false);cin.tie(0)
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()

#define FOR(i,a,b) for(ll i=a;i<=b;i++)
#define FORB(i,a,b) for(ll i=a;i>=b;i--)

#define getbit(mask,i) ((mask>>(i))&1)
#define getnum(i) (1<<(i))

#define endl "\n"
#define sz(x) (int)size(x)
#define mp make_pair
using ll = long long;
const ll MOD1 = 1e9+7;
const ll MOD2 = 998244353;
const ll MN = 1e5;


//first true float/double
double FLOAT_ERR = 1e-4;
double first_true_float(double lo, double hi, function<bool(double)> f) {
	// if none of the values in the range work, return hi + 1
	lo--;
	hi++;
	while (hi-lo > FLOAT_ERR) {
		double mid =  (lo + hi) / 2.0f;
		if (f(mid)) {
			hi = mid;
		} else {
			lo = mid;
		}
	}
	return lo;
}

int main() {
    fastio;
	//freopen("XXX.in","r",stdin);
	// freopen("XXX.out","w",stdout);
	
	ll N, L;
	cin >> N >> L;
	vector<pair<ll, ll>> stations(N);
	FOR(i,0,N-1) {
		ll y;
		cin >> stations[i].first >> y;
		stations[i].second = y*y;
	}
	double ans = first_true_float(0, L, [&](double mid) { 
		double mn=0, mx=L;
		double dd=mid*mid, xx;
		for(auto station:stations) {
			xx=sqrt(dd-station.second);
			if (station.first - xx>L) return false;
			if(station.first+xx<0) return false;

			mn = max(mn, station.first - xx);
			mx = min(mx, station.first + xx);
		}
		return mx >= mn;
	});
	cout <<  fixed << setprecision(6) << ans << endl;



}


# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 324 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 324 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 22 ms 2260 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 12 ms 2260 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 21 ms 2300 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 38 ms 3412 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 28 ms 3280 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 138 ms 12348 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 183 ms 16328 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 157 ms 14808 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 210 ms 19544 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 179 ms 17276 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 228 ms 22776 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 207 ms 19748 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 276 ms 25652 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 268 ms 24652 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 369 ms 28568 KB Output isn't correct
2 Halted 0 ms 0 KB -