#include <bits/stdc++.h>
using namespace std;
const int inf = 0x3f3f3f3f;
const long long mod = 1e9 + 7;
long long dp[25][25];
int a[30];
int dfs(int pos, int sta, bool lead, bool limit) {
  if (pos == -1) return 1;
  if (!limit && !lead && dp[pos][sta] != -1) return dp[pos][sta];
  int up = limit ? a[pos] : 9;
  long long ans = 0;
  for (int i = 0; i <= up; i++) {
    if (lead && i == 0)
      ans += dfs(pos - 1, sta, lead, limit && i == a[pos]);
    else if (sta + (i != 0) <= 3)
      ans += dfs(pos - 1, sta + (i > 0 ? 1 : 0), lead && i == 0,
                 limit && i == a[pos]);
  }
  if (!limit && !lead) dp[pos][sta] = ans;
  return ans;
}
long long solve(long long x) {
  int pos = 0;
  while (x) {
    a[pos++] = x % 10;
    x /= 10;
  }
  return dfs(pos - 1, 0, true, true);
}
int main() {
  memset(dp, -1, sizeof dp);
  int ww;
  scanf("%d", &ww);
  long long a, b;
  while (ww--) {
    scanf("%lld%lld", &a, &b);
    printf("%lld\n", solve(b) - solve(a - 1));
  }
  return 0;
}
