Submission #658005

# Submission time Handle Problem Language Result Execution time Memory
658005 2022-11-11T19:54:50 Z chjiao Mobile (BOI12_mobile) C++14
100 / 100
894 ms 32332 KB
//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;
}
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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
# Verdict Execution time Memory 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