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