답안 #658005

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
658005	2022-11-11T19:54:50 Z	chjiao	Mobile (BOI12_mobile)	C++14	100 / 100	894 ms	32332 KB

mobile

//Binary search the shortest length from the firehose

#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;
const ll MAX = LLONG_MAX;
long double FLOAT_ERR = 1e-7;
long double first_true_float(long double lo, long double hi, function<bool(long double)> f) {
	// if none of the values in the range work, return hi + 1
	lo--;
	hi++;
	while (hi-lo > FLOAT_ERR) {
		long double mid =  (lo + hi) / 2.0f;
		if (f(mid)) {
			hi = mid;
		} else {
			lo = mid;
		}
	}
	return lo;
}

int main() {
    fastio;
	//freopen("x.in","r",stdin);
	// freopen("XXX.out","w",stdout);
    int N;
    long double L;
    cin >> N >> L;
    vector<pair<long double,long double>> input(N);
    for(int i=0; i<N; i++){
        cin >> input[i].first >> input[i].second;
    }
    cout <<fixed << setprecision(7)<<first_true_float(1, 1.5e9+1, [&](long double x){
        long double left = 0;
        FOR(i,0,N-1){
            if(x*x < input[i].second*input[i].second){
                continue;
            }
            long double diviation = sqrt(x*x - input[i].second*input[i].second);
            
            if((input[i].first-diviation) <= left){
                left = max(input[i].first+diviation,left);
            }
        }
        if(left >= L){
            return true;
        } else{
         return false;
        }
    }) << endl;
}

Subtask #1
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	212 KB	Output is correct
2	Correct	0 ms	212 KB	Output is correct
3	Correct	1 ms	212 KB	Output is correct
4	Correct	1 ms	324 KB	Output is correct

Subtask #2
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	212 KB	Output is correct
2	Correct	1 ms	320 KB	Output is correct
3	Correct	1 ms	316 KB	Output is correct
4	Correct	1 ms	320 KB	Output is correct

Subtask #3
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	436 KB	Output is correct
2	Correct	4 ms	340 KB	Output is correct
3	Correct	2 ms	340 KB	Output is correct
4	Correct	2 ms	412 KB	Output is correct

Subtask #4
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	460 KB	Output is correct
2	Correct	4 ms	468 KB	Output is correct
3	Correct	4 ms	464 KB	Output is correct
4	Correct	4 ms	468 KB	Output is correct

Subtask #5
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	468 KB	Output is correct
2	Correct	6 ms	468 KB	Output is correct
3	Correct	4 ms	468 KB	Output is correct
4	Correct	4 ms	468 KB	Output is correct

Subtask #6
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	468 KB	Output is correct
2	Correct	4 ms	468 KB	Output is correct
3	Correct	4 ms	460 KB	Output is correct
4	Correct	4 ms	468 KB	Output is correct
5	Correct	4 ms	468 KB	Output is correct

Subtask #7
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	67 ms	3404 KB	Output is correct
2	Correct	62 ms	3740 KB	Output is correct
3	Correct	40 ms	2520 KB	Output is correct
4	Correct	56 ms	3660 KB	Output is correct
5	Correct	32 ms	2260 KB	Output is correct

Subtask #8
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	65 ms	3416 KB	Output is correct
2	Correct	46 ms	3284 KB	Output is correct
3	Correct	54 ms	3788 KB	Output is correct
4	Correct	58 ms	3792 KB	Output is correct
5	Correct	66 ms	4012 KB	Output is correct

Subtask #9
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	66 ms	3712 KB	Output is correct
2	Correct	70 ms	3832 KB	Output is correct
3	Correct	60 ms	3860 KB	Output is correct
4	Correct	77 ms	4456 KB	Output is correct
5	Correct	62 ms	4004 KB	Output is correct

Subtask #10
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	101 ms	4476 KB	Output is correct
2	Correct	86 ms	4456 KB	Output is correct
3	Correct	74 ms	4480 KB	Output is correct
4	Correct	74 ms	4452 KB	Output is correct
5	Correct	73 ms	4412 KB	Output is correct

Subtask #11
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	86 ms	4372 KB	Output is correct
2	Correct	81 ms	4348 KB	Output is correct
3	Correct	69 ms	4468 KB	Output is correct
4	Correct	80 ms	4460 KB	Output is correct
5	Correct	72 ms	4468 KB	Output is correct

Subtask #12
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	387 ms	16880 KB	Output is correct
2	Correct	410 ms	16976 KB	Output is correct
3	Correct	391 ms	16992 KB	Output is correct
4	Correct	398 ms	17004 KB	Output is correct
5	Correct	349 ms	16972 KB	Output is correct

Subtask #13
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	411 ms	16972 KB	Output is correct
2	Correct	480 ms	17012 KB	Output is correct
3	Correct	352 ms	16912 KB	Output is correct
4	Correct	366 ms	16992 KB	Output is correct
5	Correct	346 ms	17084 KB	Output is correct

Subtask #14
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	457 ms	20124 KB	Output is correct
2	Correct	476 ms	20004 KB	Output is correct
3	Correct	541 ms	20044 KB	Output is correct
4	Correct	459 ms	20108 KB	Output is correct
5	Correct	422 ms	20172 KB	Output is correct

Subtask #15
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	487 ms	20116 KB	Output is correct
2	Correct	570 ms	20056 KB	Output is correct
3	Correct	424 ms	20164 KB	Output is correct
4	Correct	454 ms	20092 KB	Output is correct
5	Correct	420 ms	20044 KB	Output is correct

Subtask #16
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	540 ms	23244 KB	Output is correct
2	Correct	560 ms	23184 KB	Output is correct
3	Correct	563 ms	23124 KB	Output is correct
4	Correct	546 ms	23116 KB	Output is correct
5	Correct	486 ms	23096 KB	Output is correct

Subtask #17
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	588 ms	23064 KB	Output is correct
2	Correct	647 ms	23008 KB	Output is correct
3	Correct	504 ms	22980 KB	Output is correct
4	Correct	528 ms	23004 KB	Output is correct
5	Correct	484 ms	22988 KB	Output is correct

Subtask #18
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	604 ms	26176 KB	Output is correct
2	Correct	689 ms	26084 KB	Output is correct
3	Correct	682 ms	25980 KB	Output is correct
4	Correct	606 ms	25996 KB	Output is correct
5	Correct	551 ms	25932 KB	Output is correct

Subtask #19
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	653 ms	26348 KB	Output is correct
2	Correct	730 ms	25796 KB	Output is correct
3	Correct	606 ms	25868 KB	Output is correct
4	Correct	619 ms	25812 KB	Output is correct
5	Correct	562 ms	25804 KB	Output is correct

Subtask #20
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	731 ms	32332 KB	Output is correct
2	Correct	800 ms	31972 KB	Output is correct
3	Correct	778 ms	31936 KB	Output is correct
4	Correct	740 ms	32076 KB	Output is correct
5	Correct	691 ms	31948 KB	Output is correct

Subtask #21
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	805 ms	31656 KB	Output is correct
2	Correct	894 ms	31968 KB	Output is correct
3	Correct	751 ms	31820 KB	Output is correct
4	Correct	764 ms	31852 KB	Output is correct
5	Correct	691 ms	31876 KB	Output is correct

답안 #658005

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