oj.uz

답안 #62321

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
62321 2018-07-28T05:06:44 Z Benq Fences (JOI18_fences) C++11
51 / 100
 435 ms 2352 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;

ld EPS = 1e-14;

template<class T> istream& operator>> (istream& is, complex<T>& p) {
    T value;
    is >> value; p.real(value);
    is >> value; p.imag(value);
    return is;
}

int N,S;
vector<pair<cd,cd>> p;
vector<vector<pair<int,ld>>> adj;
vector<ld> dist;
ld ans = INF;

cd reflect(cd p, cd a, cd b) { return a+conj((p-a)/(b-a))*(b-a); }
cd proj(cd p, cd a, cd b) { return (p+reflect(p,a,b))/(ld)2; }

bool bet(cd a, cd b, cd c) { return ((b-a)/(c-b)).real() > 0; }

cd closest(cd a, pair<cd,cd> b) {
    if (b.f == b.s) return b.f;
    auto x = proj(a,b.f,b.s);
    if (bet(b.f,x,b.s)) return x;
    return abs(a-b.f) < abs(a-b.s) ? b.f : b.s;
}

ld cross(cd a, cd b) { return (conj(a)*b).imag(); }
ld area(cd a, cd b, cd c) { return cross(b-a,c-a); }

cd line(cd a, cd b, cd c, cd d) {
    ld x = area(a,b,c), y = area(a,b,d);
    return (x*d-y*c)/(x-y);
}

bool equiv(cd a, cd b) {
    return abs(1-abs(a/b)) <= EPS;
}

int inter(pair<cd,cd> bes) {
    F0R(i,4) {
        auto x = line({0,0},p[i].f,bes.f,bes.s);
        if (bet(bes.f,x,bes.s) && abs(x) < abs(p[i].f) && !equiv(p[i].f,x)) return MOD;
    }
    bool swa = 0;
    if (bes.f.imag() > bes.s.imag()) swa = 1, swap(bes.f,bes.s);
    if (bes.f.imag() < 0 && bes.s.imag() >= 0) {
        auto x = line({0,0},{1,0},bes.f,bes.s);
        if (x.real() < 0) return 0;
        if (swa == 0) return 1;
        return -1;
    }
    return 0;
}

pair<cd,cd> bet(pair<cd,cd> a, pair<cd,cd> b) {
     return (abs(a.f-a.s) < abs(b.f-b.s) ? a : b);
}

pair<ld,int> dis(pair<cd,cd> a, pair<cd,cd> b) {
    pair<cd,cd> bes = {{0,0},{INF,INF}};
    bes = bet(bes,{a.f,closest(a.f,b)});
    bes = bet(bes,{a.s,closest(a.s,b)});
    bes = bet(bes,{closest(b.f,a),b.f});
    bes = bet(bes,{closest(b.s,a),b.s});
    
    int x = inter(bes);
    
    if (x == MOD) return {INF,0};
    return {abs(bes.s-bes.f),x};
}

void input() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> N >> S;
    p.pb({{S,S},{S,S}});
    p.pb({{S,-S},{S,-S}});
    p.pb({{-S,S},{-S,S}});
    p.pb({{-S,-S},{-S,-S}});
    F0R(i,N) {
        cd a,b; cin >> a >> b;
        if (a.imag() > b.imag()) swap(a,b);
        if (a.imag() < 0 && b.imag() >= 0) {
            auto x = line(a,b,{0,0},{1,0});
            if (x.real() > 0) {
                p.pb({a,x+EPS*(a-x)});
                p.pb({x,b});
                continue;
            }
        } 
        p.pb({a,b});
    }
}

void genDist(int x) {
    dist.resize(3*sz(p)); F0R(i,3*sz(p)) dist[i] = INF;
    priority_queue<pair<ld,int>,vector<pair<ld,int>>,greater<pair<ld,int>>> p;
    p.push({dist[x] = 0, x});
    while (sz(p)) {
        auto a = p.top(); p.pop();
        if (a.f > dist[a.s]) continue;
        for (auto x: adj[a.s]) if (x.s+a.f < dist[x.f])
            p.push({dist[x.f] = x.s+a.f,x.f});
    }
}

void genEdge() {
    adj.resize(3*sz(p));
    F0R(i,sz(p)) {
        F0R(j,sz(p)) if (i != j) {
            auto a = dis(p[i],p[j]);
            // cout << p[i].f << " " << p[i].s << " " << p[j].f << " " << p[j].s << " " << a.f << " " << a.s << "\n";
            if (a.f == INF) continue;
            F0R(k,3) if (0 <= k+a.s && k+a.s < 3) 
                adj[i+k*sz(p)].pb({j+(k+a.s)*sz(p),a.f});
        }
    }
}

int main() {
    input();
    genEdge();
    // exit(0);
    F0R(i,2*sz(p)) {
        genDist(i);
        ans = min(ans,dist[i+sz(p)]);
    }
    cout << fixed << setprecision(9) << ans;
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/

Compilation message

fences.cpp: In function 'void input()':
fences.cpp:119:23: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{S,S},{S,S}});
                       ^
fences.cpp:119:23: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
fences.cpp:119:23: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
fences.cpp:119:23: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
fences.cpp:120:25: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{S,-S},{S,-S}});
                         ^
fences.cpp:120:14: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{S,-S},{S,-S}});
              ^~
fences.cpp:120:25: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{S,-S},{S,-S}});
                         ^
fences.cpp:120:21: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{S,-S},{S,-S}});
                     ^~
fences.cpp:121:12: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,S},{-S,S}});
            ^~
fences.cpp:121:25: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,S},{-S,S}});
                         ^
fences.cpp:121:19: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,S},{-S,S}});
                   ^~
fences.cpp:121:25: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,S},{-S,S}});
                         ^
fences.cpp:122:12: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,-S},{-S,-S}});
            ^~
fences.cpp:122:15: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,-S},{-S,-S}});
               ^~
fences.cpp:122:20: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,-S},{-S,-S}});
                    ^~
fences.cpp:122:23: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,-S},{-S,-S}});
                       ^~

Subtask #1
18.0 / 18.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 488 KB Output is correct
3 Correct 3 ms 488 KB Output is correct
4 Correct 3 ms 488 KB Output is correct
5 Correct 3 ms 496 KB Output is correct
6 Correct 3 ms 572 KB Output is correct
7 Correct 4 ms 596 KB Output is correct
8 Correct 3 ms 708 KB Output is correct
9 Correct 3 ms 708 KB Output is correct
10 Correct 3 ms 708 KB Output is correct
11 Correct 3 ms 708 KB Output is correct
12 Correct 3 ms 708 KB Output is correct
13 Correct 3 ms 708 KB Output is correct
14 Correct 3 ms 708 KB Output is correct
15 Correct 4 ms 708 KB Output is correct
16 Correct 3 ms 716 KB Output is correct
17 Correct 3 ms 716 KB Output is correct
18 Correct 3 ms 716 KB Output is correct
19 Correct 3 ms 716 KB Output is correct
20 Correct 4 ms 716 KB Output is correct

Subtask #2
33.0 / 33.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 488 KB Output is correct
3 Correct 3 ms 488 KB Output is correct
4 Correct 3 ms 488 KB Output is correct
5 Correct 3 ms 496 KB Output is correct
6 Correct 3 ms 572 KB Output is correct
7 Correct 4 ms 596 KB Output is correct
8 Correct 3 ms 708 KB Output is correct
9 Correct 3 ms 708 KB Output is correct
10 Correct 3 ms 708 KB Output is correct
11 Correct 3 ms 708 KB Output is correct
12 Correct 3 ms 708 KB Output is correct
13 Correct 3 ms 708 KB Output is correct
14 Correct 3 ms 708 KB Output is correct
15 Correct 4 ms 708 KB Output is correct
16 Correct 3 ms 716 KB Output is correct
17 Correct 3 ms 716 KB Output is correct
18 Correct 3 ms 716 KB Output is correct
19 Correct 3 ms 716 KB Output is correct
20 Correct 4 ms 716 KB Output is correct
21 Correct 2 ms 716 KB Output is correct
22 Correct 3 ms 716 KB Output is correct
23 Correct 3 ms 716 KB Output is correct
24 Correct 3 ms 716 KB Output is correct
25 Correct 3 ms 716 KB Output is correct
26 Correct 3 ms 716 KB Output is correct
27 Correct 4 ms 716 KB Output is correct
28 Correct 3 ms 716 KB Output is correct
29 Correct 4 ms 716 KB Output is correct
30 Correct 3 ms 716 KB Output is correct
31 Correct 4 ms 716 KB Output is correct
32 Correct 3 ms 716 KB Output is correct
33 Correct 4 ms 716 KB Output is correct
34 Correct 4 ms 716 KB Output is correct
35 Correct 4 ms 716 KB Output is correct
36 Correct 3 ms 716 KB Output is correct
37 Correct 3 ms 716 KB Output is correct
38 Correct 4 ms 716 KB Output is correct
39 Correct 3 ms 716 KB Output is correct
40 Correct 3 ms 716 KB Output is correct
41 Correct 3 ms 716 KB Output is correct
42 Correct 3 ms 716 KB Output is correct
43 Correct 3 ms 716 KB Output is correct

Subtask #3
0 / 49.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 488 KB Output is correct
3 Correct 3 ms 488 KB Output is correct
4 Correct 3 ms 488 KB Output is correct
5 Correct 3 ms 496 KB Output is correct
6 Correct 3 ms 572 KB Output is correct
7 Correct 4 ms 596 KB Output is correct
8 Correct 3 ms 708 KB Output is correct
9 Correct 3 ms 708 KB Output is correct
10 Correct 3 ms 708 KB Output is correct
11 Correct 3 ms 708 KB Output is correct
12 Correct 3 ms 708 KB Output is correct
13 Correct 3 ms 708 KB Output is correct
14 Correct 3 ms 708 KB Output is correct
15 Correct 4 ms 708 KB Output is correct
16 Correct 3 ms 716 KB Output is correct
17 Correct 3 ms 716 KB Output is correct
18 Correct 3 ms 716 KB Output is correct
19 Correct 3 ms 716 KB Output is correct
20 Correct 4 ms 716 KB Output is correct
21 Correct 2 ms 716 KB Output is correct
22 Correct 3 ms 716 KB Output is correct
23 Correct 3 ms 716 KB Output is correct
24 Correct 3 ms 716 KB Output is correct
25 Correct 3 ms 716 KB Output is correct
26 Correct 3 ms 716 KB Output is correct
27 Correct 4 ms 716 KB Output is correct
28 Correct 3 ms 716 KB Output is correct
29 Correct 4 ms 716 KB Output is correct
30 Correct 3 ms 716 KB Output is correct
31 Correct 4 ms 716 KB Output is correct
32 Correct 3 ms 716 KB Output is correct
33 Correct 4 ms 716 KB Output is correct
34 Correct 4 ms 716 KB Output is correct
35 Correct 4 ms 716 KB Output is correct
36 Correct 3 ms 716 KB Output is correct
37 Correct 3 ms 716 KB Output is correct
38 Correct 4 ms 716 KB Output is correct
39 Correct 3 ms 716 KB Output is correct
40 Correct 3 ms 716 KB Output is correct
41 Correct 3 ms 716 KB Output is correct
42 Correct 3 ms 716 KB Output is correct
43 Correct 3 ms 716 KB Output is correct
44 Correct 235 ms 2264 KB Output is correct
45 Correct 201 ms 2264 KB Output is correct
46 Correct 177 ms 2264 KB Output is correct
47 Correct 162 ms 2264 KB Output is correct
48 Correct 189 ms 2264 KB Output is correct
49 Correct 217 ms 2264 KB Output is correct
50 Correct 185 ms 2264 KB Output is correct
51 Correct 195 ms 2264 KB Output is correct
52 Correct 242 ms 2264 KB Output is correct
53 Correct 169 ms 2264 KB Output is correct
54 Correct 193 ms 2264 KB Output is correct
55 Correct 277 ms 2264 KB Output is correct
56 Correct 215 ms 2264 KB Output is correct
57 Correct 159 ms 2264 KB Output is correct
58 Correct 168 ms 2264 KB Output is correct
59 Correct 195 ms 2264 KB Output is correct
60 Correct 206 ms 2264 KB Output is correct
61 Correct 253 ms 2264 KB Output is correct
62 Correct 4 ms 2264 KB Output is correct
63 Correct 4 ms 2264 KB Output is correct
64 Correct 375 ms 2264 KB Output is correct
65 Correct 435 ms 2264 KB Output is correct
66 Correct 310 ms 2264 KB Output is correct
67 Incorrect 339 ms 2352 KB Output isn't correct
68 Halted 0 ms 0 KB -