from heapq import heappop, heappush
import sys
lines = list(map(str.strip, sys.stdin.readlines()))
for line in lines[2::2]:
nums = list(map(int, line.split(" ")))
counts = {}
for x in nums:
counts[x] = 1 if x not in counts else counts[x] + 1
count_key = [(counts[key], key) for key in counts]
hq = []
for count, key in count_key:
heappush(hq, -count)
while len(hq) > 1:
a = -heappop(hq)
b = -heappop(hq)
a -= 1
b -= 1
if a: heappush(hq, -a)
if b: heappush(hq, -b)
print(0 if not hq else -hq[0])
/* ____ _ __ _ _ _
| _ \ _ __ ___ _ __ ___ | |/ /__ _ _ __ ___ __ _| | | | __ _(_)_ __
| |_) | '__/ _ \ '_ ` _ \ | ' // _` | '_ ` _ \ / _` | | _ | |/ _` | | '_ \
| __/| | | __/ | | | | | | . \ (_| | | | | | | (_| | | | |_| | (_| | | | | |
|_| |_| \___|_| |_| |_| |_|\_\__,_|_| |_| |_|\__,_|_| \___/ \__,_|_|_| |_|
*/
#include<bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef unsigned long long ull;
typedef long double lld;
#define hell 1000000007
#define PI 3.141592653589793238462
#define INF 1e18
#define vi vector<ll>
#define pb push_back
#define ppb pop_back
#define mii map<ll,ll>
#define pii pair<ll,ll>
#define mp make_pair
#define ff first
#define ss second
#define all(x) (x).begin(), (x).end()
/*____________________________________________________________________________________________________________________________________________________________________________________________________*/
vector<ll> sieve(int n) {int*arr = new int[n + 1](); vector<ll> vect; for (int i = 2; i <= n; i++)if (arr[i] == 0) {vect.push_back(i); for (int j = 2 * i; j <= n; j += i)arr[j] = 1;} return vect;}
ll mod_add(ll a, ll b, ll m) {a = a % m; b = b % m; return (((a + b) % m) + m) % m;}
ll mod_mul(ll a, ll b, ll m) {a = a % m; b = b % m; return (((a * b) % m) + m) % m;}
ll mod_sub(ll a, ll b, ll m) {a = a % m; b = b % m; return (((a - b) % m) + m) % m;}
ll expo(ll a, ll b, ll mod) {ll res = 1; while (b > 0) {if (b & 1)res = (res * a) % mod; a = (a * a) % mod; b = b >> 1;} return res;}
/*____________________________________________________________________________________________________________________________________________________________________________________________________*/
void solve()
{
ll n;
cin>>n;
mii ma;
for(ll i=0;i<n;i++){
ll x;
cin>>x;
ma[x]++;
}
priority_queue<ll> pq;
for(auto it : ma){
pq.push(it.ss);
}
while(pq.size()>1){
ll x=pq.top();
pq.pop();
ll y=pq.top();
pq.pop();
if(x>1){pq.push(x-1);}
if(y>1){pq.push(y-1);}
}
pq.push(0);
cout<<pq.top()<<endl;
return;
}
int main()
{
ios_base::sync_with_stdio(false);
int t=1;
cin>>t;
for(ll i=0;i<t;i++){
solve();
}
return 0;
}1384A - Common Prefixes | 371A - K-Periodic Array |
1542A - Odd Set | 1567B - MEXor Mixup |
669A - Little Artem and Presents | 691B - s-palindrome |
851A - Arpa and a research in Mexican wave | 811A - Vladik and Courtesy |
1006B - Polycarp's Practice | 1422A - Fence |
21D - Traveling Graph | 1559B - Mocha and Red and Blue |
1579C - Ticks | 268B - Buttons |
898A - Rounding | 1372B - Omkar and Last Class of Math |
1025D - Recovering BST | 439A - Devu the Singer and Churu the Joker |
1323A - Even Subset Sum Problem | 1095A - Repeating Cipher |
630F - Selection of Personnel | 630K - Indivisibility |
20B - Equation | 600B - Queries about less or equal elements |
1015A - Points in Segments | 1593B - Make it Divisible by 25 |
680C - Bear and Prime 100 | 1300A - Non-zero |
1475E - Advertising Agency | 1345B - Card Constructions |