#include <bits/stdc++.h>
using namespace std;
int t, len = 20;
long long c[50][50], R[2];
long long solve(int pos, int ct, string &r) {
  long long ans = 0;
  if (pos > len - 1 || ct < 0) return 0;
  if (r[pos] - '0') {
    for (int k = 0; k <= min(ct - 1, len - 1 - pos); k++)
      ans += c[k][len - 1 - pos] * pow(9, k) * (r[pos] - '0' - 1);
    for (int k = 0; k <= min(ct, len - 1 - pos); k++)
      ans += c[k][len - 1 - pos] * pow(9, k);
  }
  ans += solve(pos + 1, (r[pos] == '0' ? ct : ct - 1), r);
  return ans;
}
int main() {
  c[0][0] = 1;
  for (int j = 1; j < 50; j++) {
    c[0][j] = 1;
    for (int i = 1; i <= j; i++) c[i][j] = c[i - 1][j - 1] + c[i][j - 1];
  }
  cin >> t;
  while (t--) {
    cin >> R[0] >> R[1];
    string s0(len - to_string(R[0]).length(), '0'),
        s1(len - to_string(R[1] + 1).length(), '0');
    printf("%I64d\n", solve(0, 3, s1.append(to_string(R[1] + 1))) -
                          solve(0, 3, s0.append(to_string(R[0]))));
  }
  return 0;
}
