#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9 + 7;
const double pi = 3.141592653589793238462643383279;
vector<long long> res;
void brute(int pos, int cnt, long long cur) {
  if (pos == 18) {
    res.push_back(cur);
    return;
  }
  brute(pos + 1, cnt, cur * 10);
  if (cnt < 3) {
    for (int i = 1; i <= 9; ++i) brute(pos + 1, cnt + 1, cur * 10 + i);
  }
}
void solve() {
  long long L, R;
  cin >> L >> R;
  cout << upper_bound((res).begin(), (res).end(), R) -
              lower_bound((res).begin(), (res).end(), L);
}
signed main() {
  ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
  long long testCases = 1;
  brute(0, 0, 0);
  res.push_back(1000000000000000000);
  cin >> testCases;
  while (testCases--) {
    solve();
    cout << "\n";
  }
}
