#include <bits/stdc++.h>
using namespace std;
int dig[22];
long long dp[22][4];
long long dfs(int len, int cnt, bool limit) {
  if (cnt > 3) return 0;
  if (!len) return cnt <= 3;
  long long& v = dp[len][cnt];
  if (!limit && v != -1) return v;
  int end = limit ? dig[len] : 9;
  int ans = 0;
  for (int i = 0; i < end + 1; ++i) {
    ans += dfs(len - 1, cnt + (i != 0), limit && i == end);
  }
  if (!limit) v = ans;
  return ans;
}
long long solve(long long x) {
  int idx = 0;
  memset(dp, -1, sizeof(dp));
  ;
  while (x) {
    dig[++idx] = x % 10;
    x /= 10;
  }
  return dfs(idx, 0, 1);
}
int main(int argc, char const* argv[]) {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int t;
  cin >> t;
  while (t--) {
    long long l, r;
    cin >> l >> r;
    cout << solve(r) - solve(l - 1) << endl;
  }
  return 0;
}
