Submission #891107

#	Time	Username	Problem	Language	Result	Execution time	Memory
891107		vjudge1	Jail (JOI22_jail)	C++17	21 / 100	40 ms	10076 KiB

jail

#include <bits/stdc++.h>
using namespace std;/*
<<<<It's never too late for a new beginning in your life>>>>
Today is hard
  tomorrow will worse
  but the day after tomorrow will be the sunshine..
 
HARD WORK BEATS TALENT WHEN TALENT DOESN'T WORK HARD............
Never give up  */
//The most CHALISHKANCHIK
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define int long long
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef vector<pair<int,int> > vii;
const long long N = 1e5+50, inf = 1e18, mod = 1e9+7;
  vector<int>v[N],pred(N);
  vector<int>col(N),vis(N);
  void dfs(int x,int pr){
   vis[x] = 1;
   for(auto to:v[x]){
    if(to==pr||col[to])continue;
    dfs(to,x);
   }
  }
 void solve(){
  int n,m,k;
  cin>>n;
  for(int i = 1;i<=n;i++){
   v[i].clear();
   vis[i] = 0;
   col[i] = 0;
  }
  for(int i = 1;i<n;i++){
   int a,b;
   cin>>a>>b;
   v[a].pb(b);
   v[b].pb(a);
  }
  cin>>m;
  vector<pii>g;
  for(int i = 0;i<m;i++){
   int a,b;
   cin>>a>>b;
   g.pb({a,b});
  }
  if(m<=6){
   vector<int>ind;
   for(int i = 0;i<m;i++)ind.pb(i);

   do
   {
    //~ cout<<1<<endl;
    for(int i = 1;i<=n;i++)col[i] = 0;
    for(auto to:g){
     col[to.ff] += 1;
    }
    //~ cout<<1<<endl;
    bool flag = true;
    for(auto to:ind){
     //~ cout<<1<<endl;
     int a = g[to].ff;
     int b = g[to].ss;
     //~ cout<<to<<endl;
     col[a]--;
     for(int i = 1;i<=n;i++)vis[i] = 0;
     if(col[a]>=1){
      //~ cout<<ind[0]<<"-\n";
      flag = false;
      break;
     }
     //~ if(ind[0]==2&&ind[1]==1)
     //~ cout<<col[b]<<endl;
     dfs(a,-1);
     //~ cout<<to<<endl;
     col[b] ++;
     if(vis[b]==0){
      //~ cout<<ind[0]<<"=\n";
      flag = false;
      break;
     }
    }
    if(flag){
     //~ for(auto to:ind)cout<<to<<" ";
     cout<<"Yes\n";
     return;
    }
   } while (next_permutation(all(ind)));
   cout<<"No\n";
  }
  else{
   sort(all(g));
   set<int>st;
   for(int i = m-1;i>=0;i--){
    if(!st.empty()&&*st.begin()<g[i].ss){
     cout<<"No\n";
     return;
    }
    st.insert(g[i].ss);
   }
   cout<<"Yes\n";
  }


 }
main(){
	ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
	int t = 1;
	cin >> t;
	while(t--){
		solve();
	}
}

Compilation message (stderr)

jail.cpp: In function 'void solve()':
jail.cpp:31:11: warning: unused variable 'k' [-Wunused-variable]
   31 |   int n,m,k;
      |           ^
jail.cpp: At global scope:
jail.cpp:110:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  110 | main(){
      | ^~~~

• Subtask 1: 0 / 5
• Subtask 2: 5 / 5
• Subtask 3: 16 / 16
• Subtask 4: 0 / 28
• Subtask 5: 0 / 12
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23