#include using namespace std; using ll = long long; const ll MOD = (ll)(1e9 + 7); template T ext_gcd(T a, T b, T& x, T& y) { x = 1; y = 0; T x1 = 0, y1 = 1, a1 = a, b1 = b; while (b1) { T q = a1 / b1; tie(x, x1) = make_tuple(x1, x - q * x1); tie(y, y1) = make_tuple(y1, y - q * y1); tie(a1, b1) = make_tuple(b1, a1 - q * b1); } return a1; } template vector garner(vector a, vector m) { int k = a.size(); for (int i = 0; i < k; i++) { a[i] = (a[i] % m[i] + m[i]) % m[i]; } vector x(k); for (int i = 0; i < k; i++) { x[i] = a[i]; for (int j = 0; j < i; j++) { T tmp, r; ext_gcd(m[i], m[j], tmp, r); x[i] = (r * (x[i] - x[j]) % m[i] + m[i]) % m[i]; } } return x; } template bool crt_general(vector a, vector m, vector& ans, vector& radix) { int k = a.size(); map> mp; for (int i = 0; i < k; i++) { T tmp = m[i]; for (T j = 2; j * j <= tmp; j++) { if (tmp % j == 0) { T res = 1; while (tmp % j == 0) { tmp /= j; res *= j; } T ap = (a[i] % res + res) % res; if (mp.contains(j)) { if (mp[j].second < res) { swap(mp[j].first, ap); swap(mp[j].second, res); } if (mp[j].first % res != ap) { return false; } } else { mp[j] = make_pair(ap, res); } } } if (tmp > 1) { T ap = (a[i] % tmp + tmp) % tmp; if (mp.contains(tmp)) { if ((mp[tmp].first - ap) % tmp) { return false; } } else { mp[tmp] = make_pair(ap, tmp); } } } vector na, nm; for (auto it = mp.begin(); it != mp.end(); it++) { na.push_back(it->second.first); nm.push_back(it->second.second); } radix = nm; ans = garner(na, nm); return true; } ll mod_lcm(int n, vector y) { map pfs; for (int i = 0; i < n; i++) { for (ll j = 2; j * j <= y[i]; j++) { if (y[i] % j == 0) { ll pf = 1; while (y[i] % j == 0) { y[i] /= j; pf *= j; } if (pfs.contains(j)) { pfs[j] = max(pfs[j], pf); } else { pfs[j] = pf; } } } if (y[i] > 1 && !pfs.contains(y[i])) { pfs[y[i]] = y[i]; } } ll ret = 1; for (auto it = pfs.begin(); it != pfs.end(); it++) { ret = ret * it->second % MOD; } return ret; } int main() { cin.tie(nullptr); ios_base::sync_with_stdio(false); int n = 3; vector a(n), m(n); for (int i = 0; i < n; i++) { cin >> a[i] >> m[i]; } vector ans, radix; if (crt_general(a, m, ans, radix)) { ll res = 0, prod = 1; for (int i = 0; i < n; i++) { res = (res + ans[i] * prod) % MOD; prod = prod * radix[i] % MOD; } if (res > 0) cout << res << "\n"; else cout << mod_lcm(n, m) << "\n"; } else { cout << -1 << "\n"; } return 0; }