#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
struct IO {
	static const int inSZ = 1 << 17;
	char inBuf[inSZ], *in1, *in2;
	template<class T> inline __attribute((always_inline))
	T read() {
		if (in1 > inBuf + inSZ - 32) [[unlikely]] {
			auto len = in2 - in1;
			memcpy(inBuf, in1, len);
			in1 = inBuf, in2 = inBuf + len;
			in2 += fread(in2, 1, inSZ - len, stdin);
			if (in2 != inBuf + inSZ) *in2 = 0;
		}
		T res = 0;
		unsigned char c;
		bool neg = 0;
		while ((c = *in1++) < 48) neg = c == 45;
		while (res = res * 10 + (c - 48), (c = *in1++) >= 48);
		return neg ? -res : res;
	}
	static const int outSZ = 1 << 21;
	char outBuf[outSZ], *out;
	template<class T> inline __attribute((always_inline))
	void write(T x) {
		if (out > outBuf + outSZ - 32) [[unlikely]]
			fwrite(outBuf, 1, out - outBuf, stdout), out = outBuf;
		if (!x) return *out++ = 48, void();
		if (x < 0) *out++ = 45, x = -x;
		alignas(2) const char* digits =
		"0001020304050607080910111213141516171819"
		"2021222324252627282930313233343536373839"
		"4041424344454647484950515253545556575859"
		"6061626364656667686970717273747576777879"
		"8081828384858687888990919293949596979899";
		alignas(64) static char buf[20];
		char* p = buf + 20;
		while (x >= 10) memcpy(p -= 2, digits + x % 100 * 2, 2), x /= 100;
		if (x) *--p = 48 + x;
		auto len = buf + 20 - p;
		memcpy(out, p, len), out += len;
	}
	void init() {
		in1 = in2 = inBuf + inSZ;
		out = outBuf;
	}
	~IO() { fwrite(outBuf, 1, out - outBuf, stdout); }
} IO;
template<class T = int> inline T read() {
	return IO.read<T>();
}
template<class T> inline void write(T x, char c = ' ') {
	IO.write(x), *IO.out++ = c;
}
const int D = 20;
int T, n;
struct Edge {
	int v, nxt;
} e[2000005];
int head[2000005], len;
void Insert(int u, int v) {
	e[++len] = { v, head[u] };
	head[u] = len;
}
int ls[5000005], rs[5000005], tg[5000005], cnt;
int sta[5000005], top;
bitset<5000005> ful;
int NewNode() {
	if (!top) return ++cnt;
	int p = sta[top--];
	ls[p] = rs[p] = tg[p] = ful[p] = 0;
	return p;
}
void Pushdown(int p, int d) {
	if (d < 0) return;
	if (tg[p] >> d & 1) swap(ls[p], rs[p]);
	if (ls[p]) tg[ls[p]] ^= tg[p];
	if (rs[p]) tg[rs[p]] ^= tg[p];
	tg[p] = 0;
}
void Pushup(int p) { ful[p] = ful[ls[p]] && ful[rs[p]]; }
void Ins(int &p, int w, int d = D) {
	if (!p) p = NewNode();
	if (d < 0) return void(ful[p] = 1);
	Pushdown(p, d);
	if (w >> d & 1) Ins(rs[p], w, d - 1);
	else Ins(ls[p], w, d - 1);
	Pushup(p);
}
int Merge(int x, int y, int d = D) {
	if (!x || !y) return x | y;
	Pushdown(x, d), Pushdown(y, d);
	ls[x] = Merge(ls[x], ls[y], d - 1);
	rs[x] = Merge(rs[x], rs[y], d - 1);
	sta[++top] = y;
	if (d >= 0) Pushup(x);
	return x;
}
int Query(int p, int d = D) {
	if (!p) return 0;
	Pushdown(p, d);
	if (ful[ls[p]]) return (1 << d) | Query(rs[p], d - 1);
	return Query(ls[p], d - 1);
}
int rt[2000005], ans, tSiz[2000005];
int prt[2000005], sum[2000005];
bitset<2000005> vis;
void DFS1(int u) {
	int dst[2000005], dC = 0;
	dst[++dC] = 1;
	while (dC) {
		int u = dst[dC];
		if (vis[u]) {
			dC--;
			int p = prt[u];
			Ins(rt[u], sum[u]);
			int t = Query(rt[u]);
			if (p) {
				tg[rt[u]] ^= sum[p], tg[rt[p]] ^= t, sum[p] ^= t;
				rt[p] = Merge(rt[p], rt[u]);
			}
			continue;
		}
		vis[u] = true;
		int hs = 0;
		for (int i = head[u]; i; i = e[i].nxt) {
			int v = e[i].v;
			if (tSiz[v] > tSiz[hs]) hs = v;
		}
		for (int i = head[u]; i; i = e[i].nxt) {
			if (e[i].v == hs) continue;
			dst[++dC] = e[i].v;
		}
		if (hs) dst[++dC] = hs;
	}
}
int main() {
	IO.init();
	T = read();
	while (T--) {
		n = read();
		tSiz[1] = 1;
		for (int i = 2, p; i <= n; i++) {
			p = read(), Insert(p, i), prt[i] = p;
			tSiz[i] = 1;
		}
		for (int i = n; i > 1; i--) tSiz[prt[i]] += tSiz[i];
		DFS1(1), ans ^= Query(rt[1]);
		for (int i = 1; i <= cnt; i++) ls[i] = rs[i] = tg[i] = ful[i] = 0;
		cnt = top = len = 0;
		for (int i = 1; i <= n; i++) head[i] = 0, rt[i] = 0, sum[i] = 0, vis[i] = 0;
	}
	printf("%d\n", ans);
	return 0;
}