#include <iostream>

using namespace std;

const int64_t INF = 2e18;
int64_t safemul(int64_t a, int64_t b) {
  int64_t ret = 0;
  while(b) {
    if(b%2) ret = min(INF, ret + a);
    a = min(INF, a * 2);
    b /= 2;
  }
  return ret;
}

int main() {
  int t;
  cin >> t;
  while(t--) {
    int64_t n, d;
    cin >> n >> d;
    int ret = 0;
    int64_t amt = 1;
    while(amt < n) {
      amt = safemul(amt, d+1);
      ret++;
    }
    cout << ret << "\n";
  }
}