#include <bits/stdc++.h>
#define ll long long
#define sz(x) (int)(x).size()
using namespace std;
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
//uniform_int_distribution<int>(1000,10000)(rng)

ll binpow(ll a, ll b)
{
    ll res = 1;
    while (b > 0)
    {
        if (b & 1)
            res = res * a;
        a = a * a;
        b >>= 1;
    }
    return res;
}

ll gcd(ll a,ll b)
{
    if (b==0) return a;
    return gcd(b,a%b);
}

string to_upper(string a)
{
    for (int i=0;i<(int)a.size();++i) if (a[i]>='a' && a[i]<='z') a[i]-='a'-'A';
    return a;
}
 
string to_lower(string a)
{
    for (int i=0;i<(int)a.size();++i) if (a[i]>='A' && a[i]<='Z') a[i]+='a'-'A';
    return a;
}

constexpr long long safe_mod(long long x, long long m) {
    x %= m;
    if (x < 0) x += m;
    return x;
}

constexpr std::pair<long long, long long> inv_gcd(long long a, long long b) {
    a = safe_mod(a, b);
    if (a == 0) return {b, 0};

    // Contracts:
    // [1] s - m0 * a = 0 (mod b)
    // [2] t - m1 * a = 0 (mod b)
    // [3] s * |m1| + t * |m0| <= b
    long long s = b, t = a;
    long long m0 = 0, m1 = 1;

    while (t) {
        long long u = s / t;
        s -= t * u;
        m0 -= m1 * u;  // |m1 * u| <= |m1| * s <= b

        // [3]:
        // (s - t * u) * |m1| + t * |m0 - m1 * u|
        // <= s * |m1| - t * u * |m1| + t * (|m0| + |m1| * u)
        // = s * |m1| + t * |m0| <= b

        auto tmp = s;
        s = t;
        t = tmp;
        tmp = m0;
        m0 = m1;
        m1 = tmp;
    }
    // by [3]: |m0| <= b/g
    // by g != b: |m0| < b/g
    if (m0 < 0) m0 += b / s;
    return {s, m0};
}

std::pair<long long, long long> crt(const std::vector<long long>& r,
                                    const std::vector<long long>& m) {
    assert(r.size() == m.size());
    int n = int(r.size());
    // Contracts: 0 <= r0 < m0
    long long r0 = 0, m0 = 1;
    for (int i = 0; i < n; i++) {
        assert(1 <= m[i]);
        long long r1 = safe_mod(r[i], m[i]), m1 = m[i];
        if (m0 < m1) {
            std::swap(r0, r1);
            std::swap(m0, m1);
        }
        if (m0 % m1 == 0) {
            if (r0 % m1 != r1) return {0, 0};
            continue;
        }
        // assume: m0 > m1, lcm(m0, m1) >= 2 * max(m0, m1)

        // (r0, m0), (r1, m1) -> (r2, m2 = lcm(m0, m1));
        // r2 % m0 = r0
        // r2 % m1 = r1
        // -> (r0 + x*m0) % m1 = r1
        // -> x*u0*g = r1-r0 (mod u1*g) (u0*g = m0, u1*g = m1)
        // -> x = (r1 - r0) / g * inv(u0) (mod u1)

        // im = inv(u0) (mod u1) (0 <= im < u1)
        long long g, im;
        std::tie(g, im) = inv_gcd(m0, m1);

        long long u1 = (m1 / g);
        // |r1 - r0| < (m0 + m1) <= lcm(m0, m1)
        if ((r1 - r0) % g) return {0, 0};

        // u1 * u1 <= m1 * m1 / g / g <= m0 * m1 / g = lcm(m0, m1)
        long long x = (r1 - r0) / g % u1 * im % u1;

        // |r0| + |m0 * x|
        // < m0 + m0 * (u1 - 1)
        // = m0 + m0 * m1 / g - m0
        // = lcm(m0, m1)
        r0 += x * m0;
        m0 *= u1;  // -> lcm(m0, m1)
        if (r0 < 0) r0 += m0;
    }
    return {r0, m0};
}

void solve()
{
    ll x,y,p,q,ans=LLONG_MAX;
    cin>>x>>y>>p>>q;
    pair<ll,ll> rv;
    vector<ll> r(2),m(2);
    m[0]=2*(x+y);
    m[1]=p+q;
    for (int i=x;i<x+y;++i)
    {
        r[0]=i;
        for (int j=p;j<p+q;++j)
        {
            r[1]=j;
            rv=crt(r,m);
            if (rv.first==0&&rv.second==0)
                continue;
            if (rv.first==0)
                ans=min({ans,rv.second});
            else
                ans=min({ans,rv.first});
        }
    }
    if (ans==LLONG_MAX)
        cout<<"infinity\n";
    else
        cout<<ans<<"\n";
}

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    int t;
    cin>>t;
    while (t--)
        solve();
    return 0;
}
#include <bits/stdc++.h>
using namespace std;

int main()
{
  int N;
  cin >> N;
  
  string s;
  vector<string> S(0);
  vector<string> aS(0);
  
  int i = 0;
  int j = 0;
  
  bool imp = false;
  
  for(int i = 0; i < N; i++)
  {
    cin >> s;
    if(s.at(0) == '!') aS.push_back(s.substr(1));
    else S.push_back(s);
  }
  
  if(N == 1) cout << "satisfiable" << endl;
  else
  {
    sort(S.begin(), S.end());
    sort(aS.begin(), aS.end());
    
    for( ; ; )
    {
      if(S.size() == i || aS.size() == j)
      {
        imp = true;
        break;
      }
      
      if(S.at(i) == aS.at(j))
      {
        cout << S.at(i) << endl;
        break;
      }
      else
      {
        if(S.at(i) < aS.at(j)) i++;
        else j++;
      }
    }
  
    if(imp) cout << "satisfiable" << endl;
  }
}