Submission #1038468

#	Time	Username	Problem	Language	Result	Execution time	Memory
1038468		vjudge1	Spring cleaning (CEOI20_cleaning)	C++17	16 / 100	1086 ms	30168 KiB

cleaning

#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#pragma GCC target("popcnt")
using namespace std;

using ll = long long;
using ull = unsigned long long;
using lld = long double;
using vi = vector<int>;
using vll = vector<ll>;
using ii = pair<int,int>;
using pll = pair<ll, ll>;
using vii = vector<ii>;
using vpll = vector<pll>;

#define endl '\n'
#define all(x) x.begin(),x.end()
#define lsb(x) x&(-x)
#define gcd(a,b) __gcd(a,b)
#define sz(x) (int)x.size()
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define fls cout.flush()

#define fore(i,l,r) for(auto i=l;i<r;i++)
#define fo(i,n) fore(i,0,n)
#define forex(i,r,l) for(auto i=r; i>=l;i--)
#define ffo(i,n) forex(i,n-1,0)

bool cmin(int &a, int b){if(b<a){a=b;return 1;}return 0;}
bool cmax(int &a, int b){if(b>a){a=b;return 1;}return 0;}
void valid(ll in){cout<<((in)?"YES\n":"NO\n");}
ll lcm(ll a, ll b){return (a/gcd(a,b))*b;}
ll gauss(ll n){return (n*(n+1))/2;}
const int N = 1e5 + 7, LOG=20;
vll graph[N];
ll ni[N],szl[N],ans=0,r=0,n,q,k,x;
void dfs(ll u,ll p=0){
    szl[u]=0;
    for(ll v:graph[u]){
        if(v==p)continue;
        ni[v]=ni[u]+1;
        dfs(v, u);
        szl[u]+=szl[v];
    }
    if(sz(graph[u])==1){
        szl[u]=1;
        ans+=ni[u];
        return;
    }
    assert(szl[u]>=1);
    if(szl[u]&1){
        ans-=1ll*ni[u]*szl[u]-ni[u];
        szl[u]=1;
    }else{
        ans-=1ll*ni[u]*szl[u]-2ll*ni[u];
        szl[u]=2;
    }
}
void test_case(){
    cin>>n>>q;
    fo(i,n-1){
        ll a,b;
        cin>>a>>b;
        graph[a].pb(b);
        graph[b].pb(a);
    }
    fore(i,1,n+1)if(sz(graph[i])>1)r=i;
    while(q--){
        cin>>k;
        vll u(k);
        x=n;
        fo(i,k){
            cin>>u[i];
            graph[u[i]].pb(++x);
            graph[x].pb(u[i]);
        }
        ans=0;
        dfs(r);
        if(szl[r]!=1){
            cout<<ans<<endl;
        }else cout<<-1<<endl;
        fo(i,k)graph[u[i]].pop_back();
        fore(i,n+1,x+1)graph[i].pop_back();
    }
}
int main(){cin.tie(0)->sync_with_stdio(0);
    int t=1;
    // cin >> t;
    while(t--)test_case();
}

Compilation message (stderr)

cleaning.cpp:4: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    4 | #pragma GCC optimization ("O3")
      | 
cleaning.cpp:5: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    5 | #pragma GCC optimization ("unroll-loops")
      |

• Subtask 1: 0 / 0
• Subtask 2: 0 / 9
• Subtask 3: 0 / 9
• Subtask 4: 16 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 17
• Subtask 7: 0 / 30