oj.uz

Submission #62319

# Submission time Handle Problem Language Result Execution time Memory
62319 2018-07-28T05:03:50 Z Benq Fences (JOI18_fences) C++11
51 / 100
 469 ms 2760 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-10;

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:120:23: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{S,S},{S,S}});
                       ^
fences.cpp:120:23: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
fences.cpp:120:23: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
fences.cpp:120:23: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
fences.cpp:121:25: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{S,-S},{S,-S}});
                         ^
fences.cpp:121:14: 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:121:21: 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:122:25: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,S},{-S,S}});
                         ^
fences.cpp:122:19: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,S},{-S,S}});
                   ^~
fences.cpp:122:25: warning: narrowing conversion of 'S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,S},{-S,S}});
                         ^
fences.cpp:123:12: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,-S},{-S,-S}});
            ^~
fences.cpp:123:15: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,-S},{-S,-S}});
               ^~
fences.cpp:123:20: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,-S},{-S,-S}});
                    ^~
fences.cpp:123:23: warning: narrowing conversion of '- S' from 'int' to 'long double' inside { } [-Wnarrowing]
     p.pb({{-S,-S},{-S,-S}});
                       ^~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 456 KB Output is correct
3 Correct 2 ms 456 KB Output is correct
4 Correct 3 ms 460 KB Output is correct
5 Correct 3 ms 592 KB Output is correct
6 Correct 3 ms 592 KB Output is correct
7 Correct 3 ms 592 KB Output is correct
8 Correct 3 ms 592 KB Output is correct
9 Correct 3 ms 596 KB Output is correct
10 Correct 3 ms 600 KB Output is correct
11 Correct 2 ms 708 KB Output is correct
12 Correct 3 ms 712 KB Output is correct
13 Correct 4 ms 712 KB Output is correct
14 Correct 3 ms 712 KB Output is correct
15 Correct 2 ms 828 KB Output is correct
16 Correct 3 ms 828 KB Output is correct
17 Correct 3 ms 828 KB Output is correct
18 Correct 3 ms 828 KB Output is correct
19 Correct 3 ms 828 KB Output is correct
20 Correct 4 ms 920 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 456 KB Output is correct
3 Correct 2 ms 456 KB Output is correct
4 Correct 3 ms 460 KB Output is correct
5 Correct 3 ms 592 KB Output is correct
6 Correct 3 ms 592 KB Output is correct
7 Correct 3 ms 592 KB Output is correct
8 Correct 3 ms 592 KB Output is correct
9 Correct 3 ms 596 KB Output is correct
10 Correct 3 ms 600 KB Output is correct
11 Correct 2 ms 708 KB Output is correct
12 Correct 3 ms 712 KB Output is correct
13 Correct 4 ms 712 KB Output is correct
14 Correct 3 ms 712 KB Output is correct
15 Correct 2 ms 828 KB Output is correct
16 Correct 3 ms 828 KB Output is correct
17 Correct 3 ms 828 KB Output is correct
18 Correct 3 ms 828 KB Output is correct
19 Correct 3 ms 828 KB Output is correct
20 Correct 4 ms 920 KB Output is correct
21 Correct 4 ms 920 KB Output is correct
22 Correct 4 ms 920 KB Output is correct
23 Correct 4 ms 920 KB Output is correct
24 Correct 3 ms 920 KB Output is correct
25 Correct 3 ms 920 KB Output is correct
26 Correct 4 ms 920 KB Output is correct
27 Correct 3 ms 920 KB Output is correct
28 Correct 4 ms 920 KB Output is correct
29 Correct 4 ms 920 KB Output is correct
30 Correct 3 ms 920 KB Output is correct
31 Correct 5 ms 920 KB Output is correct
32 Correct 5 ms 920 KB Output is correct
33 Correct 4 ms 920 KB Output is correct
34 Correct 5 ms 920 KB Output is correct
35 Correct 3 ms 920 KB Output is correct
36 Correct 3 ms 920 KB Output is correct
37 Correct 4 ms 920 KB Output is correct
38 Correct 4 ms 920 KB Output is correct
39 Correct 4 ms 920 KB Output is correct
40 Correct 3 ms 920 KB Output is correct
41 Correct 4 ms 920 KB Output is correct
42 Correct 4 ms 920 KB Output is correct
43 Correct 3 ms 920 KB Output is correct

Subtask #3
0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 456 KB Output is correct
3 Correct 2 ms 456 KB Output is correct
4 Correct 3 ms 460 KB Output is correct
5 Correct 3 ms 592 KB Output is correct
6 Correct 3 ms 592 KB Output is correct
7 Correct 3 ms 592 KB Output is correct
8 Correct 3 ms 592 KB Output is correct
9 Correct 3 ms 596 KB Output is correct
10 Correct 3 ms 600 KB Output is correct
11 Correct 2 ms 708 KB Output is correct
12 Correct 3 ms 712 KB Output is correct
13 Correct 4 ms 712 KB Output is correct
14 Correct 3 ms 712 KB Output is correct
15 Correct 2 ms 828 KB Output is correct
16 Correct 3 ms 828 KB Output is correct
17 Correct 3 ms 828 KB Output is correct
18 Correct 3 ms 828 KB Output is correct
19 Correct 3 ms 828 KB Output is correct
20 Correct 4 ms 920 KB Output is correct
21 Correct 4 ms 920 KB Output is correct
22 Correct 4 ms 920 KB Output is correct
23 Correct 4 ms 920 KB Output is correct
24 Correct 3 ms 920 KB Output is correct
25 Correct 3 ms 920 KB Output is correct
26 Correct 4 ms 920 KB Output is correct
27 Correct 3 ms 920 KB Output is correct
28 Correct 4 ms 920 KB Output is correct
29 Correct 4 ms 920 KB Output is correct
30 Correct 3 ms 920 KB Output is correct
31 Correct 5 ms 920 KB Output is correct
32 Correct 5 ms 920 KB Output is correct
33 Correct 4 ms 920 KB Output is correct
34 Correct 5 ms 920 KB Output is correct
35 Correct 3 ms 920 KB Output is correct
36 Correct 3 ms 920 KB Output is correct
37 Correct 4 ms 920 KB Output is correct
38 Correct 4 ms 920 KB Output is correct
39 Correct 4 ms 920 KB Output is correct
40 Correct 3 ms 920 KB Output is correct
41 Correct 4 ms 920 KB Output is correct
42 Correct 4 ms 920 KB Output is correct
43 Correct 3 ms 920 KB Output is correct
44 Correct 211 ms 2496 KB Output is correct
45 Correct 229 ms 2496 KB Output is correct
46 Correct 196 ms 2496 KB Output is correct
47 Correct 176 ms 2496 KB Output is correct
48 Correct 174 ms 2496 KB Output is correct
49 Correct 245 ms 2496 KB Output is correct
50 Correct 181 ms 2496 KB Output is correct
51 Correct 204 ms 2496 KB Output is correct
52 Correct 216 ms 2496 KB Output is correct
53 Correct 161 ms 2496 KB Output is correct
54 Correct 175 ms 2496 KB Output is correct
55 Correct 255 ms 2496 KB Output is correct
56 Correct 238 ms 2496 KB Output is correct
57 Correct 173 ms 2496 KB Output is correct
58 Correct 212 ms 2496 KB Output is correct
59 Correct 190 ms 2496 KB Output is correct
60 Correct 208 ms 2496 KB Output is correct
61 Correct 255 ms 2496 KB Output is correct
62 Correct 3 ms 2496 KB Output is correct
63 Correct 5 ms 2496 KB Output is correct
64 Correct 396 ms 2496 KB Output is correct
65 Correct 422 ms 2496 KB Output is correct
66 Correct 281 ms 2496 KB Output is correct
67 Incorrect 469 ms 2760 KB Output isn't correct
68 Halted 0 ms 0 KB -