Submission #1144845

#	Time	Username	Problem	Language	Result	Execution time	Memory
1144845		thelegendary08	Railway (BOI17_railway)	C++17	36 / 100	103 ms	43448 KiB

railway

#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define int long long
#define vi vector<int>
#define vvi vector<vector<int>>
#define pii pair<int, int>
#define vpii vector<pair<int, int>>
#define vc vector<char>
#define vb vector<bool>
#define mii map<int,int>
#define f0r(i,n) for(int i=0;i<n;i++)
#define FOR(i,k,n) for(int i=k;i<n;i++)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define in(a) int a; cin>>a
#define in2(a,b) int a,b; cin>>a>>b
#define in3(a,b,c) int a,b,c; cin>>a>>b>>c
#define in4(a,b,c,d) int a,b,c,d; cin>>a>>b>>c>>d
#define vin(v,n); vi v(n); f0r(i,n){cin>>v[i];}
#define out(a) cout<<a<<'\n'
#define out2(a,b) cout<<a<<' '<<b<<'\n'
#define out3(a,b,c) cout<<a<<' '<<b<<' '<<c<<'\n'
#define out4(a,b,c,d) cout<<a<<' '<<b<<' '<<c<<' '<<d<<'\n'
#define vout(v) for(auto u : v){cout<<u<<' ';} cout<<'\n'
#define dout(a) cout<<a<<' '<<#a<<'\n'
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<'\n'
#define yn(x); if(x){cout<<"YES"<<'\n';}else{cout<<"NO"<<'\n';}
const int leg = 1e9 + 7;
const int mod = 998244353;
using namespace std;
const int mxn = 2e5 + 5;
vi adj[mxn];
vi tree(mxn * 4);
int v[mxn];
vi dep(mxn);
vi par(mxn);
vi head(mxn);
vi pos(mxn);
vi sz(mxn);
vi heavy(mxn);
int timer = 0;
int dfs(int node, int p){
	int sts = 1;
	par[node] = p;
	int mx = 0;
	int mxd = -1;
	for(auto u : adj[node]){
		if(u != p){
			dep[u] = dep[node] + 1;
			int s = dfs(u, node);
			sts += s;
			
			if(s > mx){
				mx = s;
				mxd = u;
			}
		}
	}
	heavy[node] = mxd;
	sz[node] = sts;
	return sts;
}
void construct(int node, int h){
	head[node] = h;
	pos[node] = timer++;
	if(heavy[node] != -1)construct(heavy[node], h);
	for(auto u : adj[node]){
		if(u != par[node] && u != heavy[node]){
			construct(u, u);
		}
	}
}
int n,m,k;
void update(int k, int x){
	k += n;
	tree[k] += x;
	for(k/=2; k>=1; k/=2){
		tree[k] = tree[k*2] + tree[k*2+1];
	}
}
int quer(int l, int r){
	//dout2(l,r);
	l += n;
	r += n;
	int ret = 0;
	while(l <= r){
		if(l % 2 == 1)ret += tree[l++];
		if(r % 2 == 0)ret += tree[r--];
		l /= 2; r /= 2;
	}
	return ret;
}
void rangeupdate(int l, int r){
	update(l, 1);
	if(r != n-1){
		update(r+1, -1);
	}
}
void rangeunupdate(int l, int r){
	update(l, -1);
	if(r != n-1){
		update(r+1, 1);
	}
}
int pointquer(int x){
	return quer(0, x);
}
void pathadd(int a, int b){
	a--; b--;
	
	for(; head[a] != head[b]; b = par[head[b]]){
		if(dep[head[a]] > dep[head[b]]){
			swap(a,b);
		}
		rangeupdate(pos[head[b]], pos[b]);
	}
	if(dep[a] > dep[b]){
		swap(a,b);
	}
	rangeupdate(pos[a], pos[b]);
	rangeunupdate(pos[a], pos[a]);
}
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	//ifstream cin(".in");
	//ofstream cout(".out");
	cin>>n>>m>>k;
	vpii edges;
	f0r(i,n-1){
		in2(a,b);
		a--;
		b--;
		adj[a].pb(b);
		adj[b].pb(a);
		edges.pb(mp(a,b));
	}
	
	dfs(0,-1);
	construct(0,0);
	//f0r(i,n)cout<<pos[i]<<' ';
	//cout<<'\n';
	mii ma;
	f0r(i,n-1){
		if(dep[edges[i].first] > dep[edges[i].second]){
			ma[edges[i].first] = i+1;
		}
		else ma[edges[i].second] = i+1;
	}
	f0r(i,m){
		in(s);
		vi w(s);
		f0r(j,s)cin>>w[j];
		f0r(j,s-1){
			pathadd(w[j], w[j+1]);
		}
	}
	vi ans;
	FOR(i, 1, n){
		if(pointquer(pos[i]) >= k){
			ans.pb(ma[i]);
		}
	}
	out(ans.size());
	for(auto u : ans)cout<<u<<' ';
	
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 15
• Subtask 3: 7 / 7
• Subtask 4: 29 / 29
• Subtask 5: 0 / 16
• Subtask 6: 0 / 25