/**     *  Author: dhruv_gheewala     *  Problem: A. Spy Detected!     *  Date:   12.04.2021     *  Time:   00:19:53   **/      #include  bits/stdc++.h    using namespace std;      #ifndef DEBUG      #define fundri 108   #define debug(...) 1729   #define endl   n       #endif      #define int int64_t      typedef pair<int, int> pii;   typedef vector<int> vi;      mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());   inline int rnd(int l = 0, int r = INT_MAX) {return uniform_int_distribution<int>(l, r)(rng);}      bool in_range(int x, int l, int r) {return l <= x && x <= r;}   template<typename H, typename ...T>void inp(H &head) {cin >> head;}   template<typename H, typename ...T>void inp(H &head, T &...tail) {cin >> head;inp(tail...);}   template<typename T>inline istream &operator >>(istream &in, vector<T> &a) {for(T &x : a)in >> x; return in;}   template<typename T, typename U>inline istream &operator >>(istream &in, pair<T, U> &a) {in >> a.first >> a.second; return in;}      // Multi-Dimension Vector   // Usage: vec<n, data-type> dp(dimention-1, dimention-2, ..., dimention-n, default = data-type())   template<int D, typename T> struct vec : public vector<vec<D - 1, T>> {       static_assert(D >= 1,  Vector dimensions must be greater than zero !! );       template<typename... Args>       vec(int n = 0, Args... args) : vector<vec<D - 1, T>>(n, vec<D - 1, T>(args...)){}   };      template<typename T> struct vec<1, T> : public vector<T> {vec(int n = 0, T val = T()) : vector<T>(n, val){}};      const int inf = 1e15;   const bool testcases = true;      const bool ready = []() -> bool {       ios_base::sync_with_stdio(false);       cin.tie(nullptr);      #ifdef DHRUV_GHEEWALA       freopen( in.txt ,  r , stdin);       freopen( out.txt ,  w , stdout);       freopen( debug.txt ,  w , stderr);   #endif          return true;   }();      void solve(int tc);   int32_t main(int32_t argc, char **argv) {       int TC = 1;       if(testcases) cin >> TC;          // Pre-Processing goes here...       for(int tc = 1; tc <= TC; ++tc) {           solve(tc);           fundri;       }       exit(0);   }      void solve(int tc) {       int n;       cin >> n;          vector<int> a(n);       cin >> a;          map<int, int> mp;       for(int x: a)           mp[x]++;          for(int i = 0; i < n; i++) {           if(mp[a[i]] == 1) {               cout << i + 1 << endl;               return;           }       }   }