func_code_string: #pragma GCC optimize( Ofast )   #pragma GCC target( avx,avx2,fma )   #include <bits/stdc++.h>      /*               GOURAB SARKAR                 */      using namespace std;      typedef   long long     ll;   typedef   long double     ld;   #define   PI      3.141592653589793238   #define   dl        n    #define   mm(a,val)    memset(a,val,sizeof(a))   #define   test               int t;                  cin >> t;              while (t--)   #define   fast()                                     ios_base::sync_with_stdio(false);              cin.tie(NULL);                                 cout.tie(NULL);      const     int mod =     1e9+7;   const     int mod1 =     1e9+9;   const     int mod2 =     998244353;      // inline void OPEN()   // {   //     #ifdef ONLINE_JUDGE   //         freopen( input.in ,  r , stdin);   //         freopen( output.in ,  w , stdout);   //     #endif   // }      inline bool comp(const pair<ll, ll> &a, const pair<ll, ll> &b) {       return (a.first > b.first);   }      inline void solve() {       fast();       ll A, B, n;       cin >> A >> B >> n;       vector<ll> a(n), b(n);       for(ll i = 0; i < n; ++i) {           cin >> a[i];       }       for(ll i = 0; i < n; ++i) {           cin >> b[i];       }       vector<pair<ll, ll> > vp;       for(ll i = 0; i < n; ++i) {           vp.push_back({a[i], b[i]});       }       sort(vp.begin(), vp.end());       // for(ll i = 0; i < n; ++i) {       //     cout << vp[i].first <<     << vp[i].second << dl;       // }       for(ll i = 0; i < n && B > 0; ++i) {           ll need = (vp[i].second % A == 0 ? vp[i].second / A : (vp[i].second / A) + 1);           ll att = (B % vp[i].first == 0 ? B / vp[i].first : (B / vp[i].first) + 1);           if(need > att) {               cout <<  NO  << dl;               return;           }           else {               B -= (need * vp[i].first);               vp[i].second = 0;           }       }       for(ll i = 0; i < n; ++i) {           if(vp[i].second > 0) {               cout <<  NO  << dl;               return;           }       }       cout <<  YES  << dl;   }      int main() {       fast();       // OPEN();       // solve();       test {           solve();       }          return 0;   }