//   //  main.cpp   //  D - Epic Transformation   //   //  Created by LiZnB on 2021/3/25.   //   #include <cstdio>   #include <cstring>   #include <algorithm>      #define ls tree[pos].l   #define rs tree[pos].r   using namespace std;      const int INF = 0x3f3f3f3f;   const int N = 200000 + 10;      int arr[N];      struct Node {       int l, r;       long long val;       int real;   };      Node max(Node a, Node b) {       if (a.val > b.val) return a;       return b;   }      struct Tree {       Node tree[N * 4];              void Built(int L, int R, int pos) {           ls = L;           rs = R;           if (L == R) {               tree[pos].val = arr[L];               tree[pos].real = L;               return;           }           int m = L + (R - L) / 2;           Built(L, m, pos << 1);           Built(m + 1, R, pos << 1 | 1);           if (tree[pos << 1].val > tree[pos << 1 | 1].val) {               tree[pos].val = tree[pos << 1].val;               tree[pos].real = tree[pos << 1].real;           } else {               tree[pos].val  = tree[pos << 1 | 1].val;               tree[pos].real = tree[pos << 1 | 1].real;           }       }              void Modify(int pos, int p, long long val) {           if (rs == p && ls == p) {               tree[pos].val += val;               return;           }           int m = ls + (rs - ls) / 2;           if (p <= m) Modify(pos << 1, p, val);           if (p > m) Modify(pos << 1 | 1, p, val);           if (tree[pos << 1].val > tree[pos << 1 | 1].val) {               tree[pos].val = tree[pos << 1].val;               tree[pos].real = tree[pos << 1].real;           } else {               tree[pos].val  = tree[pos << 1 | 1].val;               tree[pos].real = tree[pos << 1 | 1].real;           }          }              Node Query(int pos, int L, int R) {           if (ls >= L && rs <= R) {               return tree[pos];           };           int m = ls + (rs - ls) / 2;           Node ans;           ans.val = -INF;           if (m >= L) {               ans = max(Query(pos << 1, L, R), ans);           }           if (m < R) {               ans = max(Query(pos << 1 | 1, L, R), ans);           }           if (tree[pos << 1].val > tree[pos << 1 | 1].val) {               tree[pos].val = tree[pos << 1].val;               tree[pos].real = tree[pos << 1].real;           } else {               tree[pos].val  = tree[pos << 1 | 1].val;               tree[pos].real = tree[pos << 1 | 1].real;           }              return ans;       }          } T;   int d[N];   int main() {       int t;       scanf( %d , &t);       while (t--) {           int n;           scanf( %d , &n);           for (int i = 1; i <= n; i++) {               scanf( %d , &d[i]);           }           sort(d + 1, d + n + 1);           int p = 1;           arr[1] = 1;           for (int i = 2; i <= n; i++) {               if (d[i - 1] != d[i]) {                   p++;                   arr[p] = 1;               }               else {                   arr[p]++;               }           }           T.Built(1, p, 1);           int ans = n;           for (int i = 1; i <= n; i++) {               Node f1 = T.Query(1, 1, p);               T.Modify(1, f1.real, -f1.val);               Node f2 = T.Query(1, 1, p);               T.Modify(1, f1.real, f1.val);                              if (f1.val == 0 || f2.val == 0) break;               T.Modify(1, f1.real, -1);               T.Modify(1, f2.real, -1);               ans -= 2;           }           printf( %d n , ans);       }              return 0;   }