Submission #244176

#	Time	Username	Problem	Language	Result	Execution time	Memory
244176		Benq	Synchronization (JOI13_synchronization)	C++14	100 / 100	1219 ms	61816 KiB

synchronization

#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef double db; 
typedef string str; 

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

typedef vector<int> vi; 
typedef vector<ll> vl; 
typedef vector<db> vd; 
typedef vector<str> vs; 
typedef vector<pi> vpi;
typedef vector<pl> vpl; 
typedef vector<pd> vpd; 

#define mp make_pair
#define f first
#define s second
#define sz(x) (int)(x).size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend() 
#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 

#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 = 1e5+5; 
const ll INF = 1e18; 
const ld PI = acos((ld)-1);
const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1}; 
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 

template<class T> bool ckmin(T& a, const T& b) { 
	return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { 
	return a < b ? a = b, 1 : 0; } 
constexpr int pct(int x) { return __builtin_popcount(x); } 
constexpr int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x)) 
constexpr int cdiv(int a, int b) { return a/b+!(a<0||a%b == 0); } // division of a by b rounded up, assumes b > 0 
int fstTrue(function<bool(int)> f, int lo, int hi) {
	hi ++; assert(lo <= hi); // assuming f is increasing
	while (lo < hi) { // find first index such that f is true 
		int mid = (lo+hi)/2; 
		f(mid) ? hi = mid : lo = mid+1; 
	} 
	return lo;
}
template<class T> void remDup(vector<T>& v) { 
	sort(all(v)); v.erase(unique(all(v)),end(v)); }

// INPUT
template<class A> void re(complex<A>& c);
template<class A, class B> void re(pair<A,B>& p);
template<class A> void re(vector<A>& v);
template<class A, size_t SZ> void re(array<A,SZ>& a);

template<class T> 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); }
template<class H, class... T> void re(H& h, T&... t) { re(h); re(t...); }

template<class A> void re(complex<A>& c) { A a,b; re(a,b); c = {a,b}; }
template<class A, class B> void re(pair<A,B>& p) { re(p.f,p.s); }
template<class A> void re(vector<A>& x) { trav(a,x) re(a); }
template<class A, size_t SZ> void re(array<A,SZ>& x) { trav(a,x) re(a); }

// TO_STRING
#define ts to_string
str ts(char c) { return str(1,c); }
str ts(bool b) { return b ? "true" : "false"; }
str ts(const char* s) { return (str)s; }
str ts(str s) { return s; }
template<class A> str ts(complex<A> 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; }
template<class A, class B> str ts(pair<A,B> p);
template<class T> str ts(T v) { // containers with begin(), end()
	bool fst = 1; str res = "{";
	for (const auto& x: v) {
		if (!fst) res += ", ";
		fst = 0; res += ts(x);
	}
	res += "}"; return res;
}
template<class A, class B> str ts(pair<A,B> p) {
	return "("+ts(p.f)+", "+ts(p.s)+")"; }

// OUTPUT
template<class A> void pr(A x) { cout << ts(x); }
template<class H, class... T> void pr(const H& h, const T&... t) { 
	pr(h); pr(t...); }
void ps() { pr("\n"); } // print w/ spaces
template<class H, class... T> void ps(const H& h, const T&... t) { 
	pr(h); if (sizeof...(t)) pr(" "); ps(t...); }

// DEBUG
void DBG() { cerr << "]" << endl; }
template<class H, class... T> void DBG(H h, T... t) {
	cerr << ts(h); if (sizeof...(t)) cerr << ", ";
	DBG(t...); }
#ifdef LOCAL // compile with -DLOCAL
#define dbg(...) cerr << "LINE(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif

// FILE I/O
void setIn(string s) { freopen(s.c_str(),"r",stdin); }
void setOut(string s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { ios_base::sync_with_stdio(0); cin.tie(0); }
void setIO(string 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
}

vpi adj[MX];
int N,M,Q,ans[MX];
vi change[MX];
vpi bad[MX];

bool done[MX]; // processed as centroid yet
int sub[MX],cen[MX]; // subtree size, centroid anc
map<int,list<int>> to[MX], from[MX];
void dfs(int x, int p) { sub[x] = 1; 
	trav(y,adj[x]) if (!done[y.f] && y.f != p) 
		dfs(y.f,x), sub[x] += sub[y.f]; 
}
int centroid(int x) {
	dfs(x,-1); 
	for (int sz = sub[x];;) {
		pi mx = {0,0};
		trav(y,adj[x]) if (!done[y.f] && sub[y.f] < sub[x]) 
			ckmax(mx,{sub[y.f],y.f});
		if (mx.f*2 <= sz) return x; 
		x = mx.s;
	}
}
void ad(list<int>& a, list<int>& b) {
	a.splice(end(a),b); assert(!sz(b));
}
void merge(map<int,list<int>>& a, map<int,list<int>>& b) {
	if (sz(a) < sz(b)) swap(a,b);
	trav(t,b) ad(a[t.f],t.s);
	b.clear();
}

void getAll(list<int>& x, map<int,list<int>>& a, pi p) {
	while (1) {
		auto it = a.ub(p.f);
		if (it == end(a) || it->f >= p.s) break;
		ad(x,it->s); a.erase(it);
	}
}

void oops(int a, int b) {
	//dbg("OOPS",a,b);
	trav(t,adj[a]) if (!done[t.f] && t.f != b) {
		oops(t.f,a);
		trav(z,bad[t.s]) {
			{
				list<int> x; getAll(x,to[t.f],z);
				if (sz(x)) ad(to[t.f][z.f],x);
			}
			{
				list<int> x; getAll(x,from[t.f],z);
				if (sz(x)) ad(from[t.f][z.s],x);
			}
		}
		merge(to[a],to[t.f]), merge(from[a],from[t.f]);
	}
	to[a][M+1].pb(a); from[a][0].pb(a);
}

int comp[MX];

void makeLabel(int a, int b, int cnt) {
	comp[a] = cnt; //dbg("HA",a,cnt);
	trav(t,adj[a]) if (!done[t.f] && t.f != b) makeLabel(t.f,a,cnt);
}

int genLabel(int x) {
	comp[x] = 0; int cnt = 1;
	trav(y,adj[x]) if (!done[y.f]) {
		makeLabel(y.f,x,cnt++);
	}
	return cnt;
}

void gen(int CEN, int _x) { // CEN = centroid above x
	int x = centroid(_x); done[x] = 1; cen[x] = CEN; 
	sub[x] = sub[_x]; 
	//dbg("GEN",x);
	int num = genLabel(x);
	oops(x,-1);
	vi cnt(num);
	vector<pair<int,list<int>>> TO(all(to[x]));
	vector<pair<int,list<int>>> FROM(all(from[x]));
	// dbg("HAHA",sz(FROM),sz(TO));
	// dbg(TO);
	// dbg(FROM);
	int ind = 0, sum = 0;
	trav(t,TO) {
		while (ind < sz(FROM) && FROM[ind].f <= t.f) {
			trav(u,FROM[ind].s) cnt[comp[u]] ++, sum ++;
			ind ++;
		}
		trav(u,t.s) {
			ans[u] += sum;
			if (comp[u]) ans[u] -= cnt[comp[u]];
			//dbg("UH",u,ind,ans[u]);
		}
	}
	to[x].clear(), from[x].clear();
	trav(y,adj[x]) if (!done[y.f]) gen(x,y.f);
}

void init(int _N) { N = _N; FOR(i,1,N+1) done[i] = 0;
	gen(-1,1); } // start at vert 1


int main() {
	setIO(); re(N,M,Q);
	F0R(i,N-1) {
		int X,Y; re(X,Y);
		adj[X].pb({Y,i}), adj[Y].pb({X,i});
	}
	F0R(i,N-1) change[i].pb(-5);
	FOR(i,1,M+1) {
		int D; re(D); D --;
		change[D].pb(i);
	}
	F0R(i,N-1) {
		if (sz(change[i])&1) change[i].pb(M+5);
		for (int j = 0; j < sz(change[i]); j += 2) 
			bad[i].pb({change[i][j],change[i][j+1]});
	}
	F0R(i,N-1) dbg(i,bad[i]);
	init(N);
	F0R(i,Q) {
		int c; re(c);
		ps(ans[c]);
	}
	// 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
*/

Compilation message (stderr)

synchronization.cpp: In function 'int main()':
synchronization.cpp:262:26: warning: statement has no effect [-Wunused-value]
  F0R(i,N-1) dbg(i,bad[i]);
                          ^
synchronization.cpp: In function 'void setIn(std::__cxx11::string)':
synchronization.cpp:130:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
 void setIn(string s) { freopen(s.c_str(),"r",stdin); }
                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
synchronization.cpp: In function 'void setOut(std::__cxx11::string)':
synchronization.cpp:131:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
 void setOut(string s) { freopen(s.c_str(),"w",stdout); }
                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 10 / 10
• Subtask 4: 20 / 20
• Subtask 5: 40 / 40