Submission #764516

#	Time	Username	Problem	Language	Result	Execution time	Memory
764516		Zflop	Railway (BOI17_railway)	C++14	100 / 100	65 ms	25668 KiB

railway

#include <bits/stdc++.h>
using namespace std;
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;

/*
ID: 10002181
LANG: C++
TASK: lamps
*/
 
using str = string; // yay python!
using ld = long double; // or double, if TL is tight
using ll = long long;
using int64 = ll;
using db = double;
using ull = unsigned long long;
 
#define ch() getchar()
#define pc(x) putchar(x)
#define tcT template<class T
#define tcTU tcT, class U
tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
using vi = V<int>;
using vb = V<bool>;
using vpi = V<pair<int,int>>;
using vvi = V<vi>;
using vl = V<ll>;
using vd = V<ld>;
using vstr = V<str>;
 
#define all(x) begin(x), end(x)
#define sor(x) sort(all(x))
#define rev(x) reverse(all(x))
#define sz(x) (int)(x).size()
#define rall(x) x.rbegin(), x.rend()
#define AR array
 
// loops
#define F0R(i, a, b) for (int i=a; i<b;++i)
#define FOR(i, a) for (int i=0; i<a;++i)
#define FORn(i, a) for (int i=1; i<=a;++i)
#define ROF(i,a) for(int i=a-1; i >= 0;--i)
#define R0F(i,a,b) for(int i=a; i > b;--i)
#define ROFn(i,a) for(int i=a; i > 0;--i)
#define rep(a) FOR(_, a)
#define trav(i,x) for(auto& i:x)
 
// pairs
#define mp make_pair
#define pi pair <int, int>
#define f first
#define s second
 
// vectors
#define lb lower_bound
#define ub upper_bound
#define SUM(v) accumulate(all(v), 0LL)
#define MN(v) *min_element(all(v))
#define MX(v) *max_element(all(v))
#define UNIQUE(a) (a).erase(unique((a).begin(),(a).end()),(a).end())
#define eb emplace_back
#define ft front()
#define bk back()
#define ins insert
#define pf push_front
#define pb push_back
#define emt empty()
#define rsz resize
 
#define pob pop_back()
#define pof pop_front()
 
#define ts to_string
 
#define setIO()  ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
 
ll MOD = 1e9+7;
const ll MAX = 100000000000;
const ll INF = 1e18; // not too close to LLONG_MAX
const ld PI = acos((ld)-1);
 
#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
 
const int dx[4] = {1,0,-1,0}, dy[4] = {0,1,0,-1}; // for every grid problem!!
 
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;
}
 
//INPUT
#define tcTUU tcT, class ...U
tcT> void re(complex<T>& c);
tcTU> void re(pair<T,U>& p);
tcT> void re(V<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(V<T>& x) { trav(a,x) re(a); }
tcT> void rv(int n, V<T>& x) { x.rsz(n); re(x); }
 
//OUTPUT
namespace output {
	tcT> void PS(V<T>& x) { FOR(i,sz(x)) cout << x[i] << " \n"[i + 1 == sz(x)];}
	tcT> void W(pair<T,T>& x) { cout << x.f << ' ' << x.s << '\n'; }
	tcT> void PS(bool ok) { if(ok) cout << "YES\n"; else cout << "NO\n"; }
    template<class T1, class T2> void pr(const pair<T1,T2>& x);
    tcT, size_t SZ> void pr(const array<T,SZ>& x);
    tcT> void pr(const vector<T>& x);
    tcT> void pr(const set<T>& x);
    template<class T1, class T2> void pr(const map<T1,T2>& x);
 
    tcT> void pr(const T& x) { cout << x; }
    template<class Arg, class... Args> void pr(const Arg& first, const Args&... rest) {
        pr(first); pr(rest...);
    }
 
    template<class T1, class T2> void pr(const pair<T1,T2>& x) {
        pr("{",x.f,", ",x.s,"}");
    }
    tcT> void prContain(const T& x) {
        pr("{");
        bool fst = 1; trav(a,x) pr(!fst?", ":"",a), fst = 0;
        pr("}");
    }
    tcT, size_t SZ> void pr(const array<T,SZ>& x) { prContain(x); }
    tcT> void pr(const vector<T>& x) { prContain(x); }
    tcT> void pr(const set<T>& x) { prContain(x); }
    template<class T1, class T2> void pr(const map<T1,T2>& x) { prContain(x); }
 
    void ps() { pr("\n"); } // print w/ spaces
    template<class Arg> void ps(const Arg& first) { pr(first,"\n"); }
    template<class Arg, class... Args> void ps(const Arg& first, const Args&... rest) {
        pr(first," "); ps(rest...);
    }
}
 
using namespace output;
 
void setF(string fileName = "") {
	ios_base::sync_with_stdio(0); cin.tie(0);
	if((int)fileName.size()) {
		freopen((fileName+".in").c_str(), "r", stdin);
		freopen((fileName+".out").c_str(), "w", stdout);
	}
}
 
 
vb bb;
vi SIEVE(int N){ // sieve in O(N logN)
	vi pr;
	bb.rsz(N);
	bb[0] = bb[1] = true;
	vi g(N);
	F0R(i,2,N){
		if(!bb[i]){
			pr.pb(i);
			for (int j = i + i; j < N; j += i) bb[j] = true;
			}
		}
	return pr;
	}
 
 
 
template<class T> using ordset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
 
struct edge{
	int a;
	int b;
	int w;
	};
 
ll POW(ll x, ll y,ll mod){
    ll res = 1LL;
    x %= mod;
    while(y){
        if (y & 1LL)
            res *= x;
        res %= mod;
        x = (x*x) % mod;
        y >>= 1LL;
    }
    return res;
}
 
ll fact(ll x) { if(x) return x * fact(x - 1ll); return 1; }
 
vl fc;
void F(int N,ll MOD){
	fc.rsz(N + 1);
	fc[0] = 1;
	FORn(i,N) fc[i] = fc[i - 1] * i * 1ll % MOD;
	}
 
vl inv;
void I(int N,ll MOD){
	inv.rsz(N + 1);
	inv[N] = POW(fc[N],MOD - 2,MOD);
	for (int i = N; i ;--i) inv[i - 1] = inv[i] * 1ll * i % MOD;
	}
 
ll Cr(ll N,ll K,ll mod = MOD){
	if(K < 0) return 0;
	if(K > N) return 0;
	if(K == 0) return 1;
	return fc[N] * 1ll * inv[K] % mod * inv[N - K] % mod;
	}
ll Ar(ll N,ll K,ll mod){
	return fc[N] * inv[N - K] % mod;
	}
ll iv(int k,ll MOD){
  return POW(k,MOD-2,MOD);
}
ll gauss(ll x){
	return x * (x +  1) / 2;
	}
/*
 scanf("%lld", &testInteger);
 printf("%lld", testInteger);
 
 ____ ____ ____ ____ ____  ____
||f |||l |||o |||p |||p ||||y ||
||__|||__|||__|||__|||__||||__||
|/__\|/__\|/__\|/__\|/__\||/__\|
 
**/
const int NMAX = (int)1e5 + 1;
int N,M,K,t;
vi depth,A,ans;
vpi ad[NMAX];
int bj[20][NMAX];
int tin[NMAX];
void dfs(int node,int parent){
	depth[node] = depth[parent] + 1;
	bj[0][node] = parent;
	tin[node] = ++t;
	trav(x,ad[node])
		if(x.f != parent)
			dfs(x.f,node);
	}
void dfs1(int node,int parent,int id){
	trav(x,ad[node])
		if(x.f != parent){
			dfs1(x.f,node,x.s);
			A[node] += A[x.f];
			}
	//ps(node,A[node]);
	if(A[node] >= K * 2 && node != 1) ans.pb(id);
	}
int jmp(int a,int k){
	for (int i = 0; i < 20;++i) if(k & (1 << i)) a = bj[i][a];
	return a;
	}
int LCA(int a,int b){
	if(depth[a] < depth[b]) swap(a,b);
	a = jmp(a,depth[a] - depth[b]);
	if(a == b) return a;
	for (int j = 19; j >= 0;--j){
		int aT = bj[j][a];
		int bT = bj[j][b];
		if(aT != bT) {
			a = aT;
			b = bT;
			}
		}
	return bj[0][a];
	}
int dist(int a,int b){
	return depth[a] + depth[b] - 2 * depth[LCA(a,b)];
	}
void solve(){
	cin >> N >> M >> K;
	A = depth = vi(N + 1);
	FOR(i,N - 1){
		int a,b; cin >> a >> b;
		ad[a].pb({b,i + 1});
		ad[b].pb({a,i + 1});
		}
	dfs(1,0);
	for (int i = 1; i < 20;++i)
		for (int j = 1; j <= N;++j)
			bj[i][j] = bj[i - 1][bj[i - 1][j]];
	while(M--){
		int n; cin >> n;
		vi a(n); re(a);
		sort(all(a),[&] (int i,int j) { return tin[i] < tin[j]; });
		a.pb(a[0]);
		for (int i = 0; i < n;++i){
			int e = a[i];
			int w = a[i + 1];
			int c = LCA(e,w);
			A[e]++;
			A[w]++;
			A[c] -= 2;
			}
		}
	dfs1(1,0,0);
	ps(sz(ans));
	sor(ans);
	trav(x,ans) cout << x << ' ';
	}
main(){
	setIO();
	solve();
	}
 
// look out for out of bounds arrays
// And more importantly, is y a vowel? Damian:1
// <3 :L ._. <_<
// You have no idea how high I can fly
// code is my poetry

Compilation message (stderr)

railway.cpp:332:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  332 | main(){
      | ^~~~
railway.cpp: In function 'void setF(std::string)':
railway.cpp:172:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  172 |   freopen((fileName+".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
railway.cpp:173:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  173 |   freopen((fileName+".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 15 / 15
• Subtask 3: 7 / 7
• Subtask 4: 29 / 29
• Subtask 5: 16 / 16
• Subtask 6: 25 / 25