#include <bits/stdc++.h>
using namespace std;

using ll = long long;

constexpr int DIGIT = 10;
constexpr int LIM = 18;
vector<vector<ll>> power;

void prepare() {
    power = vector(DIGIT + 1, vector<ll>(LIM));
    for (int base = 1; base <= 10; base++) {
        power[base][0] = 1;
        for (int i = 1; i < LIM; i++) {
            power[base][i] = power[base][i - 1] * base;
        }
    }
}

ll answer(ll n) {
    ll ans = 9 * n;

    for (int d = 1; d <= 8; d++) {
        vector<int> digits(LIM);
        for (int i = 0; i < LIM; i++) {
            digits[i] = (n / power[10][i]) % 10;
        }

        bool is_upper = false;

        for (int i = LIM - 1; i >= 0; i--) {
            if (d < digits[i] || is_upper) {
                digits[i] = d;
                is_upper = true;
            }
        }

        ll v = 0;
        for (int i = 0; i < LIM; i++) {
            v += digits[i] * power[d + 1][i];
        }

        ans -= v;
    }

    return ans;
}

void solve(){
    ll L, R;
    cin >> L >> R;
    cout << answer(R) - answer(L - 1) << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int T;
    cin >> T;
    prepare();
    while (T--) {
        solve();
    }
}