#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <bits/stdc++.h>
using namespace std;
using namespace __gnu_pbds;
template <class T> using Tree = tree<T, null_type, less<T>,
rb_tree_tag, tree_order_statistics_node_update>;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using db = double;
using str = string; // yay python!
using pi = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;
using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<db>;
using vs = vector<str>;
using vpi = vector<pi>;
using vpl = vector<pl>;
using vpd = vector<pd>;
#define tcT template<class T
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
// pairs
#define mp make_pair
#define f first
#define s second
// vectors
#define sz(x) (int)(x).size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define ft front()
#define bk back()
#define pf push_front
#define pb push_back
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
// loops
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)
const int MOD = 1e9+7; // 998244353
const int MX = 2e5+5;
const ll INF = 1e18; // not too close to LLONG_MAX
const int IINF = 1e9;
const ld PI = acos((ld)-1);
const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1}; // for every grid problem!!
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count());
// helper funcs
constexpr int pct(int x) { return __builtin_popcount(x); } // # of bits set
constexpr int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x))
ll cdiv(ll a, ll b) { return a/b+((a^b)>0&&a%b); } // divide a by b rounded up
ll fdiv(ll a, ll b) { return a/b-((a^b)<0&&a%b); } // divide a by b rounded down
tcT> bool ckmin(T& a, const T& b) {
return b < a ? a = b, 1 : 0; } // set a = min(a,b)
tcT> bool ckmax(T& a, const T& b) {
return a < b ? a = b, 1 : 0; }
#define tcTU tcT, class U
tcTU> T fstTrue(T lo, T hi, U f) {
hi ++; assert(lo <= hi); // assuming f is increasing
while (lo < hi) { // find first index such that f is true
T mid = lo+(hi-lo)/2;
f(mid) ? hi = mid : lo = mid+1;
}
return lo;
}
tcTU> T lstTrue(T lo, T hi, U f) {
lo --; assert(lo <= hi); // assuming f is decreasing
while (lo < hi) { // find first index such that f is true
T mid = lo+(hi-lo+1)/2;
f(mid) ? lo = mid : hi = mid-1;
}
return lo;
}
tcT> void remDup(vector<T>& v) { // sort and remove duplicates
sort(all(v)); v.erase(unique(all(v)),end(v)); }
tcTU> void erase(T& t, const U& u) { // don't erase
auto it = t.find(u); assert(it != end(t));
t.erase(u); } // element that doesn't exist from (multi)set
// INPUT
#define tcTUU tcT, class ...U
tcT> void re(complex<T>& c);
tcTU> void re(pair<T,U>& p);
tcT> void re(vector<T>& v);
tcT, size_t SZ> void re(AR<T,SZ>& a);
tcT> void re(T& x) { cin >> x; }
void re(db& d) { str t; re(t); d = stod(t); }
void re(ld& d) { str t; re(t); d = stold(t); }
tcTUU> void re(T& t, U&... u) { re(t); re(u...); }
tcT> void re(complex<T>& c) { T a,b; re(a,b); c = {a,b}; }
tcTU> void re(pair<T,U>& p) { re(p.f,p.s); }
tcT> void re(vector<T>& x) { trav(a,x) re(a); }
tcT, size_t SZ> void re(AR<T,SZ>& x) { trav(a,x) re(a); }
// TO_STRING
#define ts to_string
str ts(char c) { return str(1,c); }
str ts(const char* s) { return (str)s; }
str ts(str s) { return s; }
str ts(bool b) {
#ifdef LOCAL
return b ? "true" : "false";
#else
return ts((int)b);
#endif
}
tcT> str ts(complex<T> c) {
stringstream ss; ss << c; return ss.str(); }
str ts(vector<bool> v) {
str res = "{"; F0R(i,sz(v)) res += char('0'+v[i]);
res += "}"; return res; }
template<size_t SZ> str ts(bitset<SZ> b) {
str res = ""; F0R(i,SZ) res += char('0'+b[i]);
return res; }
tcTU> str ts(pair<T,U> p);
tcT> str ts(T v) { // containers with begin(), end()
#ifdef LOCAL
bool fst = 1; str res = "{";
for (const auto& x: v) {
if (!fst) res += ", ";
fst = 0; res += ts(x);
}
res += "}"; return res;
#else
bool fst = 1; str res = "";
for (const auto& x: v) {
if (!fst) res += " ";
fst = 0; res += ts(x);
}
return res;
#endif
}
tcTU> str ts(pair<T,U> p) {
#ifdef LOCAL
return "("+ts(p.f)+", "+ts(p.s)+")";
#else
return ts(p.f)+" "+ts(p.s);
#endif
}
// OUTPUT
tcT> void pr(T x) { cout << ts(x); }
tcTUU> void pr(const T& t, const U&... u) {
pr(t); pr(u...); }
void ps() { pr("\n"); } // print w/ spaces
tcTUU> void ps(const T& t, const U&... u) {
pr(t); if (sizeof...(u)) pr(" "); ps(u...); }
// DEBUG
void DBG() { cerr << "]" << endl; }
tcTUU> void DBG(const T& t, const U&... u) {
cerr << ts(t); if (sizeof...(u)) cerr << ", ";
DBG(u...); }
#ifdef LOCAL // compile with -DLOCAL, chk -> fake assert
#define dbg(...) cerr << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#define chk(...) if (!(__VA_ARGS__)) cerr << "Line(" << __LINE__ << ") -> function(" \
<< __FUNCTION__ << ") -> CHK FAILED: (" << #__VA_ARGS__ << ")" << "\n", exit(0);
#else
#define dbg(...) 0
#define chk(...) 0
#endif
// FILE I/O
void setIn(str s) { freopen(s.c_str(),"r",stdin); }
void setOut(str s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
void setIO(str s = "") {
unsyncIO();
// cin.exceptions(cin.failbit);
// throws exception when do smth illegal
// ex. try to read letter into int
if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
}
struct custom_hash {
static uint64_t splitmix64(uint64_t x) {
// http://xorshift.di.unimi.it/splitmix64.c
x += 0x9e3779b97f4a7c15;
x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
return x ^ (x >> 31);
}
size_t operator()(uint64_t x) const {
static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
return splitmix64(x + FIXED_RANDOM);
}
};
int N;
ll PERM = 0;
void shift(vpl& p){
pl poi = mp(INF, INF);
trav(a, p)
ckmin(poi, a);
trav(a, p)
a = mp(a.f - poi.f, a.s - poi.s);
}
void rotate(vpl& p){
vpl ret;
trav(a, p)
ret.pb(mp(a.s, -a.f));
p = ret;
}
void reflect(vpl& p){
vpl ret;
trav(a, p)
ret.pb(mp(a.f, -a.s));
p = ret;
}
bool equiv(vpl& A, vpl& B){
set<pl> con;
trav(a, A)
con.insert(a);
trav(a, B)
if(con.count(a) == 0)
return false;
return (sz(A) == sz(B));
}
bool check(vpl& A, vpl& B){
shift(A);
shift(B);
F0R(i, 4){
rotate(A);
shift(A);
if(equiv(A, B)){
cout << i << endl;
return true;
}
}
reflect(A);
F0R(i, 4){
rotate(A);
shift(A);
if(equiv(A, B))
return true;
}
return false;
}
set<pair<pl, pl>> s;
map<pair<pl, pl>, pi> ind;
bool flip;
bool solve(vpl p){
ll dist = 0;
int i = 0;
s.clear();
ind.clear();
F0R(a, sz(p)){
while(i < sz(p)){
if(dist + abs(p[(i + 1) % N].s - p[i].s + p[(i + 1) % N].f - p[i].f) >= PERM / 2)
break;
dist += abs(p[(i + 1) % N].s - p[i].s + p[(i + 1) % N].f - p[i].f);
i++;
}
if(i == sz(p))
break;
while(i < sz(p)){
pair<pl, pl> x = mp(p[a], p[(a + 1) % N]);
pair<pl, pl> y = mp(p[i], p[(i + 1) % N]);
if(x.f.s == x.s.s && y.f.s == y.s.s){
if((x.f.f > x.s.f) != (y.f.f > y.s.f)){
if(y.f.f > y.s.f){
ll init = y.f.f - (PERM / 2 - dist);
if(init >= x.f.f && (init - x.f.f) % 2 == 0 &&
(init + x.f.f) / 2 <= y.f.f &&
(init + x.f.f) / 2 <= x.s.f && (init + x.f.f) / 2 >= y.s.f)
s.insert(mp(mp((init + x.f.f) / 2, min(x.f.s, y.f.s)), mp((init + x.f.f) / 2, max(x.f.s, y.f.s))));
}
else{
ll init = y.f.f + (PERM / 2 - dist);
if(init <= x.f.f && (x.f.f - init) % 2 == 0 &&
(init + x.f.f) / 2 >= y.f.f &&
(init + x.f.f) / 2 >= x.s.f && (init + x.f.f) / 2 <= y.s.f)
s.insert(mp(mp((init + x.f.f) / 2, min(x.f.s, y.f.s)), mp((init + x.f.f) / 2, max(x.f.s, y.f.s))));
}
}
}
if(dist + abs(p[(i + 1) % N].s - p[i].s + p[(i + 1) % N].f - p[i].f)
>= PERM / 2 + abs(p[(a + 1) % N].s - p[a].s + p[(a + 1) % N].f - p[a].f))
break;
dist += abs(p[(i + 1) % N].s - p[i].s + p[(i + 1) % N].f - p[i].f);
i++;
}
dist -= abs(p[(a + 1) % N].s - p[a].s + p[(a + 1) % N].f - p[a].f);
}//true = start
priority_queue<pl, vector<pl>, greater<pl>> Q1a;
priority_queue<pl, vector<pl>, greater<pl>> Q2a;
F0R(a, sz(p)){
pair<pl, pl> temp = mp(p[a], p[(a + 1) % N]);
if(temp.f.s == temp.s.s){
if(temp.f > temp.s)
swap(temp.f, temp.s);
Q1a.push(temp.s);
Q2a.push(temp.f);
}
}
Tree<int> c2;
trav(e, s){
bool good = false;
while(sz(Q2a) && Q2a.top().f < e.f.f){
auto t2 = Q2a.top(); Q2a.pop();
c2.insert(t2.s);
}
while(sz(Q1a) && Q1a.top().f < e.f.f){
auto temp = Q1a.top(); Q1a.pop();
c2.erase(temp.s);
}
while(sz(Q2a) && Q2a.top().f == e.f.f){
auto t2 = Q2a.top(); Q2a.pop();
c2.insert(t2.s);
}
int V1 = c2.order_of_key(e.f.s), V2 = c2.order_of_key(e.s.s);
if(V1 == V2 - 1)
good = true;
if(good){
vpl A1, A;
vpl B1, B;
int fst = -1;
int sec = -1;
F0R(a, sz(p)){
if(p[a].s == p[(a + 1) % N].s && p[a].s == e.f.s){
if(min(p[a].f, p[(a + 1) % N].f) <= e.f.f && max(p[a].f, p[(a + 1) % N].f) >= e.f.f){
fst = a;
break;
}
}
}
F0R(a, sz(p)){
if(p[a].s == p[(a + 1) % N].s && p[a].s == e.s.s){
if(min(p[a].f, p[(a + 1) % N].f) <= e.s.f && max(p[a].f, p[(a + 1) % N].f) >= e.s.f){
sec = a;
break;
}
}
}
A1.pb(e.f);
for(int a = (fst + 1) % N;;a = (a + 1) % N){
A1.pb(p[a]);
if(a == sec)
break;
}
A1.pb(e.s);
B1.pb(e.s);
for(int a = (sec + 1) % N;;a = (a + 1) % N){
B1.pb(p[a]);
if(a == fst)
break;
}
B1.pb(e.f);
A1.erase(unique(all(A1)), A1.end());
B1.erase(unique(all(B1)), B1.end());
F0R(a, sz(A1)){
if((A1[a].f == A1[(a + 1) % sz(A1)].f && A1[a].s != A1[(a + 1) % sz(A1)].s &&
A1[(a + 1) % sz(A1)].f != A1[(a + 2) % sz(A1)].f && A1[(a + 1) % sz(A1)].s == A1[(a + 2) % sz(A1)].s)
|| (A1[a].f != A1[(a + 1) % sz(A1)].f && A1[a].s == A1[(a + 1) % sz(A1)].s &&
A1[(a + 1) % sz(A1)].f == A1[(a + 2) % sz(A1)].f && A1[(a + 1) % sz(A1)].s != A1[(a + 2) % sz(A1)].s)){
A.pb(A1[(a + 1) % sz(A1)]);
}
}
F0R(a, sz(B1)){
if((B1[a].f == B1[(a + 1) % sz(B1)].f && B1[a].s != B1[(a + 1) % sz(B1)].s &&
B1[(a + 1) % sz(B1)].f != B1[(a + 2) % sz(B1)].f && B1[(a + 1) % sz(B1)].s == B1[(a + 2) % sz(B1)].s)
|| (B1[a].f != B1[(a + 1) % sz(B1)].f && B1[a].s == B1[(a + 1) % sz(B1)].s &&
B1[(a + 1) % sz(B1)].f == B1[(a + 2) % sz(B1)].f && B1[(a + 1) % sz(B1)].s != B1[(a + 2) % sz(B1)].s)){
B.pb(B1[(a + 1) % sz(B1)]);
}
}
bool found = check(A, B);
if(found){
if(!flip)
cout << e.f.f << " " << e.f.s << " " << e.s.f << " " << e.s.s << endl;
else
cout << e.f.s << " " << e.f.f << " " << e.s.s << " " << e.s.f << endl;
return true;
}
return false;
}
}
return false;
}
int main(){
setIO();
cin >> N;
vpl poly(N);
F0R(a, N)
cin >> poly[a].f >> poly[a].s;
F0R(a, N)
PERM += abs(poly[(a + 1) % N].f - poly[a].f)
+ abs(poly[(a + 1) % N].s - poly[a].s);
if(PERM % 2 == 1){
cout << "NO" << endl;
return 0;
}
if(solve(poly))
return 0;
F0R(a, N)
swap(poly[a].f, poly[a].s);
flip = true;
if(!solve(poly))
cout << "NO" << endl;
// you should actually read the stuff at the bottom
}
/* stuff you should look for
* int overflow, array bounds
* special cases (n=1?)
* do smth instead of nothing and stay organized
* WRITE STUFF DOWN
* DON'T GET STUCK ON ONE APPROACH
*/
Compilation message
demarcation.cpp: In function 'void setIn(str)':
demarcation.cpp:190:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
190 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
demarcation.cpp: In function 'void setOut(str)':
demarcation.cpp:191:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
191 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
1808 KB |
Output isn't correct - Not enough numbers in output |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
364 KB |
Output isn't correct - Not enough numbers in output |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
364 KB |
Output isn't correct - Not enough numbers in output |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
1828 KB |
Output isn't correct - Not enough numbers in output |
| 2 |
Halted |
0 ms |
0 KB |
- |
