1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
|
#include <geometry/sortAround.cpp>
namespace details {
// Liegt p auf der Strecke a-b?
bool pointInLineSegment(pt a, pt b, pt p) {
if (cross(a, b, p) != 0) return false;
auto dist = norm(a - b);
return norm(a - p) < dist && norm(b - p) < dist;
}
// Test auf Streckenschnitt zwischen a-b und c-d.
// (nur intern)
bool lineSegmentIntersection(pt a, pt b, pt c, pt d) {
if (cross(a, b, c) == 0 && cross(a, b, d) == 0) {
return pointInLineSegment(a,b,c) ||
pointInLineSegment(a,b,d) ||
pointInLineSegment(c,d,a) ||
pointInLineSegment(c,d,b);
}
return ccw(a, b, c) * ccw(a, b, d) < 0 &&
ccw(c, d, a) * ccw(c, d, b) < 0;
}
}
namespace Random {
vector<ll> partition(ll n, std::size_t k){//min = 0;
n += k;
vector<ll> res = Random::distinct<ll>(k-1, 1, n);
sort(all(res));
res.emplace_back(n);
ll last = 0;
for (std::size_t i = 0; i < k; i++) {
res[i] -= last;
last += res[i];
res[i]--;
}
return res;
}
vector<pt> convex(int n, ll dim) {
binomial_distribution<int> binomial(n - 2, 0.5);
while (true) {
int left = 1 + binomial(Random::rng);
int down = 1 + binomial(Random::rng);
auto x = Random::partition(2 * dim - 2, left);
auto y = Random::partition(2 * dim - 2, down);
for (auto& z : x) z = -z;
for (auto& z : y) z = -z;
for (auto z : Random::partition(2 * dim - 2, n - left)) x.push_back(z);
for (auto z : Random::partition(2 * dim - 2, n - down)) y.push_back(z);
auto itX = std::partition(x.begin(), x.end(), [](ll z){return z == 0;});
auto itY = std::partition(y.begin(), y.end(), [](ll z){return z != 0;});
if (distance(x.begin(), itX) + distance(itY, y.end()) > n) continue;
shuffle(itX, x.end(), Random::rng);
if (itX != x.begin()) shuffle(y.begin(), itY, Random::rng);
vector<pt> dirs(n);
for (size_t i = 0; i < dirs.size(); i++) {
dirs[i] = pt(x[i], y[i]);
}
sortAround(0, dirs);
vector<pt> res = {{0, 0}};
ll maxX = 0;
ll maxY = 0;
for (auto dir : dirs) {
pt tmp(real(res.back()) + real(dir),
imag(res.back()) + imag(dir));
maxX = std::max<ll>(maxX, real(tmp));
maxY = std::max<ll>(maxY, imag(tmp));
res.emplace_back(tmp);
}
res.pop_back();
for (auto& point : res) {
point = pt(real(point) + dim - 1 - maxX,
imag(point) + dim - 1 - maxY);
}
bool strict = true;
for (int i = 0; i < n; i++) strict &= cross(res[i], res[(i + 1) % n], res[(i + 2) % n]) != 0;
if (strict) return res;
}
}
vector<pt> polygon(int n, ll dim) {
while (true) {
vector<pt> ps = points<pt::value_type>(n, -dim, dim);
bool coolinear = false;
for (int i = 0; i < n; i++) {
for (int j = 0; j < i; j++) {
for (int k = 0; k < j; k++) {
coolinear |= cross(ps[i], ps[j], ps[k]) == 0;
}
}
}
if (coolinear) continue;
bool changed;
do {
changed = false;
for (int i = 0; i < n && !changed; i++) {
for (int j = i + 1; j < n && !changed; j++) {
if (details::lineSegmentIntersection(ps[i], ps[(i+1) % n], ps[j], ps[(j+1) % n])) {
reverse(ps.begin() + i + 1, ps.begin() + j + 1);
changed = true;
}
}
}
} while (changed);
return ps;
}
}
pt integerPoint(ll range) {
return pt(integer<ll>(-range, range),
integer<ll>(-range, range));
}
vector<pt> integerPoints(std::size_t n, ll range) {
vector<pt> res(n);
for (auto& p : res) p = integerPoint(range);
return res;
}
array<pt, 2> line(ll range) {
pt a = integerPoint(range);
pt b = a;
while (b == a) b = integerPoint(range);
return {a, b};
}
array<pt, 3> triangle(ll range) {
pt a = integerPoint(range);
pt b = a;
while (b == a) b = integerPoint(range);
pt c = a;
while (ccw(a, b, c) == 0) c = integerPoint(range);
return {a, b, c};
}
}
|