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#include 
   
    using namespace std;const int N = 3e5 + 9;typedef long long ll;unordered_map 
    
      m;ll cnt;ll n, t;ll ans[N];struct xxxx{       ll x;    ll sum;}bcj[N];ll Find(ll x){   	ll r = x, j, k = x;	while(bcj[r].x != r) r = bcj[r].x;	while(k != r)	{   		j = bcj[k].x;		bcj[k].x = r;		k = j;	}	return r;}void Union(ll a,ll b){   	a = Find(a);	b = Find(b);	if(a != b)// 根节点不同才加到另一个集合    {           bcj[b].x = a;        bcj[a].sum += bcj[b].sum;        // 因为是把a当根节点，所以一定要把 b 的加到 a 里面 ！！！        // 不能加反了！！！    }}int main(){   	cin >> t;	while(t--)	{   		cin >> n;		cnt = 0;		m.clear();		memset(ans,0,sizeof(ans));		for(ll i = 1; i <= N-9; ++i) bcj[i].x = i, bcj[i].sum = 1;		ll a, b;		for(ll i = 1; i <= n; ++i)		{   			scanf("%lld %lld", &a, &b);			if(m[a] == NULL) m[a] = ++cnt;			a = m[a];			if(m[b] == NULL) m[b] = ++cnt;			b = m[b];			Union(a, b);		}		for(ll i = 1; i <= cnt; ++i) Find(i);		ll Max = 0;		ll ttt = 0;		for(int i = 1; i <= cnt; ++i)        {               ans[bcj[i].x]++;            //cout << bcj[i].sum << "   " << bcj[i].x <