#include<bits/stdc++.h>

using namespace std;

void solve(){
	int n;
	cin >> n;

	vector<int> fa(n), cnt(n);
	vector<vector<int>> adj(n);
	fa[0] = -1;

	for(int u = 1; u < n; u++){
		int v; cin >> v; v--;
		adj[v].push_back(u);
		fa[u] = v;
		cnt[v]++; 
	}

	int cur = 1;
	queue<int> q;
	for(int i = 0; i < n; i++){
		if(cnt[i] == 0) 
			q.push(i);
		else
			cur += cnt[i] - 1; 
	}
	int ans = cur;
	// cout << ans << "\n";

	while(q.size() > 1){
		vector<int> tmp;
		while(!q.empty()){
			int u = q.front();
			q.pop();
			cnt[fa[u]]--;
			if(cnt[fa[u]] == 0)
				tmp.push_back(fa[u]);
			else
				cur--;
		}

		cur++;
		ans=min(ans, cur);

		for(auto i : tmp) q.push(i);
	}

	cout << ans << "\n";
}

int main(){
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	int t; cin >> t;
	while(t--) solve();

	return 0;
}