Submission #464413

#	Time	Username	Problem	Language	Result	Execution time	Memory
464413		Khizri	Railway (BOI17_railway)	C++17	23 / 100	291 ms	524292 KiB

railway

#include <bits/stdc++.h>
using namespace std;
//------------------------------DEFINE------------------------------
//******************************************************************
#define IOS ios_base::sync_with_stdio(false); cin.tie(0),cout.tie(0)
#define ll long long
#define pb push_back		 
#define F first																 
#define S second 															 
#define INF 1e18
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pii pair<int,int>
#define pll pair<ll,ll>
#define OK cout<<"Ok"<<endl;
#define MOD (ll)(1e9+7)
#define endl "\n"
//******************************************************************
//----------------------------FUNCTION------------------------------
//******************************************************************
ll gcd(ll a,ll b){
	if(a>b) swap(a,b);
	if(a==0) return a+b;
	return gcd(b%a,a);
}
ll lcm(ll a,ll b){
	return a/gcd(a,b)*b;
}
bool is_prime(ll n){
	ll k=sqrt(n);
	if(n==2) return true;
	if(n<2||n%2==0||k*k==n) return false;
	for(int i=3;i<=k;i+=2){
		if(n%i==0){
			return false;
		}
	}
	return true;
}
//*****************************************************************
//--------------------------MAIN-CODE------------------------------
const int mxn=1e5+5,lg=30;
int t=1,n,m,k,x,y,up[mxn][lg],tin[mxn],tout[mxn],timer,node[mxn],color[mxn],say[mxn];
vector<pii>vt[mxn];
vector<int>arr[mxn];
void dfs(int u,int p,int q){
	tin[u]=++timer;
	up[u][0]=p;
	for(int i=1;i<lg;i++){
		up[u][i]=up[up[u][i-1]][i-1];
	}
	arr[u]=arr[p];
	if(q!=-1){
		arr[u].pb(q);
	}
	for(pii v:vt[u]){
		if(v.F!=p){
			dfs(v.F,u,v.S);
		}
	}
	tout[u]=++timer;
}
bool funk(int u,int v){
	return tin[u]<=tin[v]&&tout[u]>=tout[v];
}
int lca(int u,int v){
	if(funk(u,v)){
		return u;
	}
	for(int i=lg-1;i>=0;i--){
		if(!funk(up[u][i],v)){
			u=up[u][i];
		}
	}
	return up[u][0];
}
void solve(){
	cin>>n>>m>>k;
	for(int i=1;i<n;i++){
		cin>>x>>y;
		vt[x].pb({y,i});
		vt[y].pb({x,i});
	}
	dfs(1,1,-1);
	for(int qq=1;qq<=m;qq++){
		cin>>x;
		for(int i=1;i<=x;i++){
			cin>>node[i];
		}
		for(int i=2;i<=x;i++){
			int q=lca(node[i-1],node[i]);
			int u=node[i-1],v=node[i];
			for(int i=arr[q].size();i<arr[u].size();i++){
				int edge=arr[u][i];
				if(color[edge]!=qq){
					color[edge]=qq;
					say[edge]++;
				}
			}
			for(int i=arr[q].size();i<arr[v].size();i++){
				int edge=arr[v][i];
				if(color[edge]!=qq){
					color[edge]=qq;
					say[edge]++;
				}
			}
		}
	}
	int ans=0;
	for(int i=1;i<n;i++){
		if(say[i]>=k){
			ans++;
		}
	}
	cout<<ans<<endl;
	for(int i=1;i<n;i++){
		if(say[i]>=k){
			cout<<i<<' ';
		}
	}
	cout<<endl;
}
int main(){
	IOS;
	//cin>>t;
	while(t--){
		solve();
	}
	return 0;
}

Compilation message (stderr)

railway.cpp: In function 'void solve()':
railway.cpp:93:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   93 |    for(int i=arr[q].size();i<arr[u].size();i++){
      |                            ~^~~~~~~~~~~~~~
railway.cpp:100:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  100 |    for(int i=arr[q].size();i<arr[v].size();i++){
      |                            ~^~~~~~~~~~~~~~

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