Submission #758561

# Submission time Handle Problem Language Result Execution time Memory
758561 2023-06-14T22:19:35 Z NK_ Special graph (IZhO13_specialg) C++17
100 / 100
142 ms 32268 KB
#include <bits/stdc++.h>

using namespace std;

/////////////////////// MACROS ////////////////////////////////////////////
using ll = long long;
using ld = long double;
using db = double;
using str = string;

using pi = pair<int,int>;
using pl = pair<ll,ll>;

using vi = vector<int>;
using vl = vector<ll>;
using vs = vector<str>;
using vc = vector<char>;
using vpi = vector<pi>;
using vpl = vector<pl>;

#define tcT template<class T
#define tcTU tcT, class U
tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
tcTU> using PR = pair<T,U>;
tcTU> using umap = unordered_map<T, U>;
tcT> using uset = unordered_set<T>;
tcT> using mset = multiset<T>;

#define mp make_pair
#define f first
#define s second

#define sz(x) int((x).size())
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define rsz resize
#define ins insert
#define ft front()
#define bk back()
#define ppb pop_back()
#define ppf pop_front()
#define pb push_back
#define eb emplace_back
#define pf push_front

#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 rep(a) F0R(_, a)
#define each(a,x) for (auto& a: x)

/////////////////////// IMPORANT VARS /////////////////////////////////////

const int MOD = 1e9+7; // 998244353;
const int MX = 2e5+5;
const ll INFL = ll(3e18)+10;
const int INF = int(1e9)+10;
const ld PI = acos((ld)-1);
const int dx[4] = {1,0,-1,0}, dy[4] = {0,1,0,-1};
tcT> using pqg = priority_queue<T,vector<T>,greater<T>>;
tcT> using pql = priority_queue<T,vector<T>,less<T>>;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define nl '\n'

constexpr int pct(int x) { return __builtin_popcount(x); } // # of bits set
constexpr int bits(int x) { 
	return x == 0 ? 0 : 31-__builtin_clz(x); }
constexpr int p2(int x) { return 1<<x; }
constexpr int msk2(int x) { return p2(x)-1; }
 
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; }
 
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(it); } // element that doesn't exist from (multi)set


// #include <ext/pb_ds/assoc_container.hpp>
// using namespace __gnu_pbds;

// tcT> using iset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>; 
// #define ook order_of_key
// #define fbo find_by_order

// struct chash { 
// 	const uint64_t C = ll(2e18*PI)+71;
// 	const int RANDOM = rng();
// 	ll operator()(ll x) const {
// 		return __builtin_bswap64((x^RANDOM)*C); }
// };
// template<class K,class V> using um = unordered_map<K,V,chash>;
// template<class K,class V> using ht = gp_hash_table<K,V,chash>;
// template<class K,class V> V get(ht<K,V>& u, K x) {
// 	auto it = u.find(x); return it == end(u) ? 0 : it->s; }

/////////////////////// OUPUT /////////////////////////////////////////////
#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
}
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
}

tcTU> str ts(V<pair<T, U>> v) {
	#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
}

tcT> str ts(T v) {
	#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
}

///////////////////////// DEBUG ///////////////////////////////////////////
#define tcTUU tcT, class ...U
void DBG() { cerr << "]" << "\e[0m" << endl; }
tcTUU> void DBG(const T& t, const U&... u) {
	cerr << ts(t); if (sizeof...(u)) cerr << ", ";
	DBG(u...); }
#ifdef LOCAL
	#define dbg(...) cerr << "\e[1m" << "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 unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
void setPrec() { cout << fixed << setprecision(15); }
void setIn(str s) { freopen(s.c_str(),"r",stdin); }
void setOut(str s) { freopen(s.c_str(),"w",stdout); }
void setIO(str s = "") {
	unsyncIO(); setPrec();
	#ifndef LOCAL	
		if (sz(s)) setIn(s+".in"), setOut(s+".out"); // for USACO
	#endif
}

///////////////////////// TEMPLATE ABOVE //////////////////////////////////

// REMEMBER
// - Don't Focus On Only One Approach
// - Read And Understand Problem Fully
// - Think Of Edges Cases
// - Implement Carefully
// - Always Check For Overflows
// - Reset Global Variables
// - Look At The Bigger Picture
// - Don't Get Discouraged, You Can Pull It Back

struct TreeTour {
    vi st, en, par, dep;
    V<vi> adj; int t;
    void init(int N) {
    	t = 0;
        st = en = par = dep = vi(N);
        adj = V<vi>(N);
    }
 	
    void ae(int a, int b) { adj[a].pb(b); }
    void dfs(int x) {
		st[x] = t++;
        each(y,adj[x]) {
            par[y] = x; dep[y] = dep[x]+1; dfs(y); }
        en[x] = t-1;
    	dbg(x, st[x], en[x]);
    }   
    void gen(int R) { par[R] = R; dep[R] = 0; dfs(R); } 
    bool isAnc(int a, int b) { return (st[a] <= st[b] && en[b] <= en[a]); }
};

tcT> struct BIT {
	int N; V<T> data;
	void init(int _N) { N = _N; data = V<T>(N, 0); }
	void add(int p, T x) { for (++p;p<=N;p+=p&-p) data[p-1] ^= x; }
	void add(int l, int r, T x) { add(l, x); add(r+1, x); }
	T get(int r) { T s = 0; for(++r;r;r-=r&-r)s^=data[r-1]; return s; }
};

const ll BIG = 1e15 + 7;

ll get() { return (rng() + 5LL * MOD) % MOD; }
ll rnd() { return (get() * get()) % BIG; }

void solve() {
	int N; cin >> N;
	vi A(N); each(x, A) { cin >> x; --x; }
	vi deg(N); each(x, A) if (x != -1) deg[x]++;

	int Z = count(begin(A), end(A), -1);
	dbg(Z);

	set<int> C; V<vi> cyc;
	map<int, int> COMP;

	vi vis(N);
	F0R(x, N) {
		int u = x;
		vi seen;
		while(!vis[u]) {
			vis[u] = 1; seen.pb(u);
			if (vis[u] == 2 || A[u] == -1) break;
			u = A[u];
		}

		if (vis[u] == 2 || A[u] == -1) {
			each(v, seen) vis[v] = 2;
			continue;
		}

		vis = vi(N, 0);
		cyc.pb({});
		while(!vis[u]) {
			vis[u] = 1;
			cyc.bk.pb(u);
			u = A[u];
		}

		dbg(cyc);

		int c = cyc.bk.bk;
		// F0R(i, sz(cyc.bk)) if (deg[A[cyc.bk[i]]] > 1) {
		// 	c = cyc.bk[i];
		// 	rotate(begin(cyc.bk), begin(cyc.bk) + i + 1, end(cyc.bk));
		// }

		A[c] = -1;
		C.ins(c);
		COMP[c] = sz(cyc) - 1;
		each(v, cyc.bk) vis[v] = 2;
	}

	int M = sz(cyc);
	dbg(C, cyc);
	map<int, int> TO;

	BIT<ll> B; B.init(2*N+1);
	TreeTour T; T.init(2*N+1);
	int cur = N;

	F0R(u, N) {
		dbg(A[u], u);
		if (A[u] != -1) T.ae(A[u], u);
		
		if (C.count(u)) {
			int comp = COMP[u];
			int prv = u;
			F0R(i, sz(cyc[comp])) {
				T.ae(cur, prv);
				dbg(cur, prv, cyc[comp][i]);
				prv = cur;
				TO[cyc[comp][i]] = cur++;
			}
		}
	}

	F0R(u, N) if (A[u] == -1) {
		int U = u;
		if (C.count(u)) U = TO[U];

		dbg(U);
		T.gen(U);
		B.add(T.st[U], T.en[U], rnd());
	}

	int Q; cin >> Q;
	rep(Q) {
		int t; cin >> t;
		if (t == 1) {
			int u; cin >> u; --u;

			B.add(T.st[u], T.en[u], rnd());
			if (TO.find(u) != TO.end()) {
				B.add(T.st[TO[u]], T.en[TO[u]], rnd());
			}

		} 
		if (t == 2) {
			int u, v; cin >> u >> v; --u, --v;

			BACK:;

			if (T.dep[u] < T.dep[v]) {
				if (TO.find(v) != TO.end()) { v = TO[v]; goto BACK; }
				cout << -1 << nl;
				continue;
			}

			dbg(u, v);
			ll ru = B.get(T.st[u]), rv = B.get(T.st[v]);
			dbg(ru, rv, T.isAnc(v, u));
			if (ru != rv || !T.isAnc(v, u)) {
				if (TO.find(v) != TO.end()) { v = TO[v]; goto BACK; }
				cout << -1 << nl;
				continue;
			} 

			cout << T.dep[u] - T.dep[v] << nl;
		}
	}
}

int main() {
	setIO(); 

	int TT = 1;
	// cin >> TT;

	rep(TT) solve();
	
	exit(0-0);
}

Compilation message

specialg.cpp: In member function 'void TreeTour::dfs(int)':
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:237:6: note: in expansion of macro 'dbg'
  237 |      dbg(x, st[x], en[x]);
      |      ^~~
specialg.cpp: In function 'void solve()':
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:262:2: note: in expansion of macro 'dbg'
  262 |  dbg(Z);
      |  ^~~
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:290:3: note: in expansion of macro 'dbg'
  290 |   dbg(cyc);
      |   ^~~
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:305:2: note: in expansion of macro 'dbg'
  305 |  dbg(C, cyc);
      |  ^~~
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:313:3: note: in expansion of macro 'dbg'
  313 |   dbg(A[u], u);
      |   ^~~
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:321:5: note: in expansion of macro 'dbg'
  321 |     dbg(cur, prv, cyc[comp][i]);
      |     ^~~
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:332:3: note: in expansion of macro 'dbg'
  332 |   dbg(U);
      |   ^~~
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:360:4: note: in expansion of macro 'dbg'
  360 |    dbg(u, v);
      |    ^~~
specialg.cpp:194:19: warning: statement has no effect [-Wunused-value]
  194 |  #define dbg(...) 0
      |                   ^
specialg.cpp:362:4: note: in expansion of macro 'dbg'
  362 |    dbg(ru, rv, T.isAnc(v, u));
      |    ^~~
specialg.cpp:261:6: warning: unused variable 'Z' [-Wunused-variable]
  261 |  int Z = count(begin(A), end(A), -1);
      |      ^
specialg.cpp:304:6: warning: unused variable 'M' [-Wunused-variable]
  304 |  int M = sz(cyc);
      |      ^
specialg.cpp: In function 'void setIn(str)':
specialg.cpp:201:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  201 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
specialg.cpp: In function 'void setOut(str)':
specialg.cpp:202:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  202 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 2 ms 468 KB Output is correct
2 Correct 2 ms 592 KB Output is correct
3 Correct 2 ms 640 KB Output is correct
4 Correct 5 ms 596 KB Output is correct
5 Correct 2 ms 464 KB Output is correct
6 Correct 9 ms 872 KB Output is correct
7 Correct 9 ms 872 KB Output is correct
8 Correct 9 ms 948 KB Output is correct
9 Correct 8 ms 852 KB Output is correct
10 Correct 9 ms 980 KB Output is correct
11 Correct 142 ms 32184 KB Output is correct
12 Correct 64 ms 15072 KB Output is correct
13 Correct 73 ms 19712 KB Output is correct
14 Correct 59 ms 13512 KB Output is correct
15 Correct 61 ms 15860 KB Output is correct
16 Correct 66 ms 15504 KB Output is correct
17 Correct 88 ms 24556 KB Output is correct
18 Correct 90 ms 24596 KB Output is correct
19 Correct 96 ms 24656 KB Output is correct
20 Correct 136 ms 32268 KB Output is correct