#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }

////////////////////////////////////////////////////////////////////////////////
template <unsigned M_> struct ModInt {
  static constexpr unsigned M = M_;
  unsigned x;
  constexpr ModInt() : x(0U) {}
  constexpr ModInt(unsigned x_) : x(x_ % M) {}
  constexpr ModInt(unsigned long long x_) : x(x_ % M) {}
  constexpr ModInt(int x_) : x(((x_ %= static_cast<int>(M)) < 0) ? (x_ + static_cast<int>(M)) : x_) {}
  constexpr ModInt(long long x_) : x(((x_ %= static_cast<long long>(M)) < 0) ? (x_ + static_cast<long long>(M)) : x_) {}
  ModInt &operator+=(const ModInt &a) { x = ((x += a.x) >= M) ? (x - M) : x; return *this; }
  ModInt &operator-=(const ModInt &a) { x = ((x -= a.x) >= M) ? (x + M) : x; return *this; }
  ModInt &operator*=(const ModInt &a) { x = (static_cast<unsigned long long>(x) * a.x) % M; return *this; }
  ModInt &operator/=(const ModInt &a) { return (*this *= a.inv()); }
  ModInt pow(long long e) const {
    if (e < 0) return inv().pow(-e);
    ModInt a = *this, b = 1U; for (; e; e >>= 1) { if (e & 1) b *= a; a *= a; } return b;
  }
  ModInt inv() const {
    unsigned a = M, b = x; int y = 0, z = 1;
    for (; b; ) { const unsigned q = a / b; const unsigned c = a - q * b; a = b; b = c; const int w = y - static_cast<int>(q) * z; y = z; z = w; }
    assert(a == 1U); return ModInt(y);
  }
  ModInt operator+() const { return *this; }
  ModInt operator-() const { ModInt a; a.x = x ? (M - x) : 0U; return a; }
  ModInt operator+(const ModInt &a) const { return (ModInt(*this) += a); }
  ModInt operator-(const ModInt &a) const { return (ModInt(*this) -= a); }
  ModInt operator*(const ModInt &a) const { return (ModInt(*this) *= a); }
  ModInt operator/(const ModInt &a) const { return (ModInt(*this) /= a); }
  template <class T> friend ModInt operator+(T a, const ModInt &b) { return (ModInt(a) += b); }
  template <class T> friend ModInt operator-(T a, const ModInt &b) { return (ModInt(a) -= b); }
  template <class T> friend ModInt operator*(T a, const ModInt &b) { return (ModInt(a) *= b); }
  template <class T> friend ModInt operator/(T a, const ModInt &b) { return (ModInt(a) /= b); }
  explicit operator bool() const { return x; }
  bool operator==(const ModInt &a) const { return (x == a.x); }
  bool operator!=(const ModInt &a) const { return (x != a.x); }
  friend std::ostream &operator<<(std::ostream &os, const ModInt &a) { return os << a.x; }
};
////////////////////////////////////////////////////////////////////////////////


int C[256];
int N;

namespace modP {

template <int M> ModInt<M> run() {
  using Mint = ModInt<M>;
  Mint val = 0;
  for (int i = 0; i < 256; ++i) {
    val += Mint(C[i]) * Mint(i);
  }
  for (int n = 1; n <= N; ++n) {
    if (val.x == 0 || val.x == 1) {
      break;
    }
    val = val.pow(n);
  }
  return val;
}

}  // modP

namespace mod257 {

using Mint = ModInt<257>;

int mod(int x) {
  return (x >= 1) ? (1 + (x - 1) % 256) : x;
}
int bn[12][12];
int crt[6][257], nxt[6][257];

bitset<257> dp[2][257];

bool canZero() {
  const int im = max_element(C, C + 256) - C;
  if (N >= 2 * 257 && N - C[im] >= 257) {
    return true;
  }
  int s = 0;
  for (int r = 0; r < 257; ++r) {
    dp[s][r].reset();
  }
  dp[s][0][0] = true;
  for (int i = 0; i < N; ++i) if (i != im) {
    for (int r = 0; r < 257; ++r) {
      dp[s ^ 1][r].reset();
    }
    for (int r = 0; r < 257; ++r) {
      for (int a = 0; a <= C[i]; ++a) {
        const int rr = Mint(r + (C[i] - 2 * a) * i).x;
        dp[s ^ 1][rr] |= dp[s][r] << a;
      }
    }
    s ^= 1;
  }
  for (int r = 0; r < 257; ++r) for (int k = 0; k < 257; ++k) if (dp[s][r][k]) {
    const int am = N / 2 - k;
    if (0 <= am && am <= C[im]) {
      if (!Mint(r + (C[im] - 2 * am) * im)) {
        return true;
      }
    }
  }
  return false;
}

Mint run() {
// cerr<<"canZero = "<<canZero()<<endl;
  if (N <= 11) {
    for (int n = 0; n <= N; ++n) {
      bn[n][0] = bn[n][n] = 1;
      for (int k = 1; k < n; ++k) {
        bn[n][k] = mod(bn[n - 1][k - 1] + bn[n - 1][k]);
      }
    }
    int fac = 1;
    for (int n = 1; n <= N / 2; ++n) {
      if (!fac) break;
      fac = mod(fac * n);
    }
    for (int n = 1; n <= N - N / 2; ++n) {
      if (!fac) break;
      fac = mod(fac * n);
    }
// cerr<<"N = "<<N<<": fac = "<<fac<<endl;
    memset(crt, 0, sizeof(crt));
    crt[0][0] = fac;
    for (int i = 0; i < 256; ++i) if (C[i]) {
      memset(nxt, 0, sizeof(nxt));
      for (int k = 0; k <= N / 2; ++k) {
        for (int r = 0; r < 257; ++r) {
          for (int a = 0; a <= C[i] && k + a <= N / 2; ++a) {
            const int rr = Mint(r + (C[i] - 2 * a) * i).x;
            nxt[k + a][rr] = mod(nxt[k + a][rr] + crt[k][r] * bn[C[i]][a]);
          }
        }
      }
      memcpy(crt, nxt, sizeof(nxt));
    }
    Mint ans = 1;
    for (int r = 0; r < 257; ++r) {
      ans *= Mint(r).pow(crt[N / 2][r]);
    }
    return ans;
  } else {
    return canZero() ? 0 : 1;
  }
}

}  // mod257

int main() {
  for (int numCases; ~scanf("%d", &numCases); ) { for (int caseId = 1; caseId <= numCases; ++caseId) {
    memset(C, 0, sizeof(C));
    int K;
    scanf("%d", &K);
    for (; K--; ) {
      int i;
      scanf("%d", &i);
      scanf("%d", &C[i]);
    }
    N = 0;
    for (int i = 0; i < 256; ++i) {
      N += C[i];
    }
    
    const auto ans3 = modP::run<3>();
    const auto ans5 = modP::run<5>();
    const auto ans17 = modP::run<17>();
    const auto ans257 = mod257::run();
// cerr<<"ans3 = "<<ans3<<endl;
// cerr<<"ans5 = "<<ans5<<endl;
// cerr<<"ans17 = "<<ans17<<endl;
// cerr<<"ans257 = "<<ans257<<endl;
    for (int x = ans257.x; ; x += 257) {
      if (!(ans3 - x) && !(ans5 - x) && !(ans17 - x)) {
        printf("%d\n", x);
        break;
      }
    }
  }
#ifndef LOCAL
  break;
#endif
  }
  return 0;
}