답안 #1064682

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1064682	2024-08-18T16:51:31 Z	daviedu	Mobile (BOI12_mobile)	C++17	100 / 100	379 ms	41808 KB

mobile

#include <bits/stdc++.h>
using namespace std;

#define fastio ios_base::sync_with_stdio(0); cin.tie(0)
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define ll long long
#define ld long double

struct P{
    ll x, y;
};

void dbg_out() { cerr << endl; }
template <typename H, typename... T>
void dbg_out(H h, T... t) { cerr << ' ' << h; dbg_out(t...); }
#define dbg(...) { cerr << #__VA_ARGS__ << ':'; dbg_out(__VA_ARGS__); }

ld border(ld x, ld y, ld a, ld b){
    return (a*a + b*b - x*x - y*y) / (2*a - 2*x);
}

ld dist(ld x, ld y, ld point){
    return sqrtl(y*y + (point-x)*(point-x));
}

signed main(){
    fastio;
    int n, r;
    cin >> n >> r;
    stack<pair<ld, ld>> st;
    // this will be useful for simplifying implementation later
    st.push({-2e9, -2e9});
    ld a, b, x, y;
    for (int i=0; i<n; i++){
        cin >> a >> b;
        if (b < 0) b = -b;
        
        while (!st.empty() && st.top().first == a && st.top().second > b) st.pop();

        while ((int)st.size() > 1){
            tie(x, y) = st.top();
            st.pop();

            // if prev is not a useless point, put it back and stop
            if (border(x, y, a, b) > border(st.top().first, st.top().second, x, y)){
                st.push({x, y});
                break;
            }
        }

        st.push({a, b});
    }
    ld ans=0;
    ld right=r;
    while ((int)st.size() > 1){
        tie(a, b) = st.top();
        st.pop();
        tie(x, y) = st.top();
        ld left = border(x, y, a, b);
        
        // not in some interesting range yet
        if (left >= right) continue;

        ans = max(ans, dist(a, b, right));
        ans = max(ans, dist(a, b, max(left, (ld)0)));
        
        // from here onwards we will be looking at non interesting ranges
        if (left <= 0) break;
        right = left;
    }

    cout << fixed << setprecision(13);
    cout << ans << '\n';
}

Subtask #1
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	344 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	348 KB	Output is correct
4	Correct	0 ms	348 KB	Output is correct

Subtask #2
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	348 KB	Output is correct
2	Correct	1 ms	348 KB	Output is correct
3	Correct	0 ms	348 KB	Output is correct
4	Correct	0 ms	348 KB	Output is correct

Subtask #3
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	344 KB	Output is correct
2	Correct	1 ms	348 KB	Output is correct
3	Correct	1 ms	348 KB	Output is correct
4	Correct	1 ms	544 KB	Output is correct

Subtask #4
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	760 KB	Output is correct
2	Correct	2 ms	348 KB	Output is correct
3	Correct	2 ms	348 KB	Output is correct
4	Correct	2 ms	464 KB	Output is correct

Subtask #5
4.0 / 4.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	348 KB	Output is correct
2	Correct	2 ms	564 KB	Output is correct
3	Correct	2 ms	344 KB	Output is correct
4	Correct	2 ms	544 KB	Output is correct

Subtask #6
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	344 KB	Output is correct
2	Correct	2 ms	348 KB	Output is correct
3	Correct	2 ms	348 KB	Output is correct
4	Correct	3 ms	472 KB	Output is correct
5	Correct	2 ms	348 KB	Output is correct

Subtask #7
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	23 ms	1368 KB	Output is correct
2	Correct	24 ms	1352 KB	Output is correct
3	Correct	16 ms	1132 KB	Output is correct
4	Correct	27 ms	1624 KB	Output is correct
5	Correct	14 ms	856 KB	Output is correct

Subtask #8
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	24 ms	1116 KB	Output is correct
2	Correct	24 ms	1092 KB	Output is correct
3	Correct	27 ms	1372 KB	Output is correct
4	Correct	30 ms	1628 KB	Output is correct
5	Correct	32 ms	1884 KB	Output is correct

Subtask #9
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	26 ms	3924 KB	Output is correct
2	Correct	26 ms	1608 KB	Output is correct
3	Correct	26 ms	3676 KB	Output is correct
4	Correct	39 ms	2356 KB	Output is correct
5	Correct	28 ms	1372 KB	Output is correct

Subtask #10
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	36 ms	1884 KB	Output is correct
2	Correct	36 ms	1620 KB	Output is correct
3	Correct	29 ms	1884 KB	Output is correct
4	Correct	39 ms	2236 KB	Output is correct
5	Correct	34 ms	1600 KB	Output is correct

Subtask #11
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	35 ms	3920 KB	Output is correct
2	Correct	33 ms	1872 KB	Output is correct
3	Correct	37 ms	1780 KB	Output is correct
4	Correct	42 ms	2372 KB	Output is correct
5	Correct	33 ms	1732 KB	Output is correct

Subtask #12
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	156 ms	21116 KB	Output is correct
2	Correct	168 ms	8016 KB	Output is correct
3	Correct	188 ms	7508 KB	Output is correct
4	Correct	186 ms	9808 KB	Output is correct
5	Correct	183 ms	7096 KB	Output is correct

Subtask #13
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	173 ms	8536 KB	Output is correct
2	Correct	194 ms	8784 KB	Output is correct
3	Correct	153 ms	9296 KB	Output is correct
4	Correct	216 ms	9664 KB	Output is correct
5	Correct	168 ms	7760 KB	Output is correct

Subtask #14
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	181 ms	25112 KB	Output is correct
2	Correct	190 ms	9900 KB	Output is correct
3	Correct	188 ms	9040 KB	Output is correct
4	Correct	229 ms	12112 KB	Output is correct
5	Correct	203 ms	8276 KB	Output is correct

Subtask #15
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	195 ms	10068 KB	Output is correct
2	Correct	201 ms	9996 KB	Output is correct
3	Correct	175 ms	9308 KB	Output is correct
4	Correct	226 ms	12116 KB	Output is correct
5	Correct	211 ms	9048 KB	Output is correct

Subtask #16
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	212 ms	29412 KB	Output is correct
2	Correct	222 ms	11092 KB	Output is correct
3	Correct	214 ms	10580 KB	Output is correct
4	Correct	259 ms	13880 KB	Output is correct
5	Correct	228 ms	9296 KB	Output is correct

Subtask #17
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	235 ms	11856 KB	Output is correct
2	Correct	224 ms	11452 KB	Output is correct
3	Correct	217 ms	12976 KB	Output is correct
4	Correct	257 ms	13652 KB	Output is correct
5	Correct	236 ms	10576 KB	Output is correct

Subtask #18
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	242 ms	33536 KB	Output is correct
2	Correct	257 ms	12844 KB	Output is correct
3	Correct	253 ms	11956 KB	Output is correct
4	Correct	300 ms	16048 KB	Output is correct
5	Correct	277 ms	11604 KB	Output is correct

Subtask #19
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	260 ms	13396 KB	Output is correct
2	Correct	258 ms	12876 KB	Output is correct
3	Correct	272 ms	13912 KB	Output is correct
4	Correct	330 ms	15916 KB	Output is correct
5	Correct	297 ms	11856 KB	Output is correct

Subtask #20
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	307 ms	41808 KB	Output is correct
2	Correct	313 ms	15952 KB	Output is correct
3	Correct	307 ms	14932 KB	Output is correct
4	Correct	369 ms	19540 KB	Output is correct
5	Correct	339 ms	13888 KB	Output is correct

Subtask #21
5.0 / 5.0

#	결과	실행 시간	메모리	Grader output
1	Correct	325 ms	16808 KB	Output is correct
2	Correct	334 ms	15844 KB	Output is correct
3	Correct	300 ms	17748 KB	Output is correct
4	Correct	379 ms	19780 KB	Output is correct
5	Correct	350 ms	15188 KB	Output is correct

답안 #1064682

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