func_code_string: #include <bits/stdc++.h>   using namespace std;   long long q;   long long n, k, a, b;   int main() {     cin >> q;     while (q--) {       cin >> k >> n >> a >> b;       long long l = 0, r = n, mid, ans = -1;       while (l <= r) {         mid = (l + r) / 2;         if (mid * a + (n - mid) * b >= k)           r = mid - 1;         else           l = mid + 1, ans = mid;       }       cout << ans << endl;     }     return 0;   }   