#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pli = pair<ll, int>;
using vi = vector<int>;
using vl = vector<ll>;
using vpii = vector<pii>;
template <class T>
inline bool ckmin(T& a, const T& b) {
  return b < a ? a = b, 1 : 0;
}
template <class T>
inline bool ckmax(T& a, const T& b) {
  return b > a ? a = b, 1 : 0;
}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const char nl = '\n';
const int mxN = 2e5 + 10;
const int MOD = 1e9 + 7;
const ll infLL = 1e18;
const ld eps = 1e-6;
ll dp[20][10][2][5];
vl nums;
void calc(int p = 0, int z = 0, ll num = 0) {
  if (p == 18) {
    nums.push_back(num);
    return;
  }
  calc(p + 1, z, num * 10);
  if (z < 3)
    for (int i = (1); i < (10); i++) calc(p + 1, z + 1, num * 10 + i);
}
void solve() {
  ll l, r;
  cin >> l >> r;
  cout << upper_bound(nums.begin(), nums.end(), r) -
              lower_bound(nums.begin(), nums.end(), l)
       << nl;
}
int32_t main() {
  cin.tie(0)->sync_with_stdio(0);
  calc();
  int t;
  cin >> t;
  nums.push_back(1e18);
  sort(nums.begin(), nums.end());
  while (t--) {
    solve();
  }
}
