#include <bits/stdc++.h>
using namespace std;
vector<int> num;
long long dp[405][250][2];
long long digitDP(int idx, long long nonZeroCnt, bool isSmall) {
  if (nonZeroCnt > 3) return 0;
  if (idx == (int)num.size()) return 1;
  if (dp[idx][nonZeroCnt][isSmall] != -1) return dp[idx][nonZeroCnt][isSmall];
  long long res = 0;
  int lmt = isSmall ? 9 : num[idx];
  for (int dgt = 0; dgt <= lmt; dgt++) {
    res +=
        digitDP(idx + 1, (dgt > 0) + nonZeroCnt, ((dgt < num[idx]) | isSmall));
  }
  return dp[idx][nonZeroCnt][isSmall] = res;
}
long long call(long long n) {
  num.clear();
  while (n > 0L) {
    num.push_back((int)(n % 10L));
    n /= 10L;
  }
  reverse(num.begin(), num.end());
  memset(dp, -1, sizeof dp);
  return digitDP(0, 0, 0);
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long t, l, r;
  cin >> t;
  while (t--) {
    cin >> l >> r;
    cout << call(r) - call(l - 1) << '\n';
  }
  return 0;
}
