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

using int64 = long long;

long long pw[11][20];

long long count_leq(long long x, int k) {
    if (x <= 0) return 0;

    string s = to_string(x);
    int n = s.size();

    long long ans = 0;

    for (int len = 1; len < n; len++) {
        ans += 1LL * k * pw[k + 1][len - 1];
    }

    for (int i = 0; i < n; i++) {
        int cur = s[i] - '0';
        int rem = n - 1 - i;

        int start = (i == 0 ? 1 : 0);

        for (int d = start; d < cur; d++) {
            if (d <= k) {
                ans += pw[k + 1][rem];
            }
        }

        if (cur > k) {
            return ans;
        }
    }

    return ans + 1;
}

long long F(long long x) {
    if (x <= 0) return 0;

    long long res = 0;
    long long prev = 0;

    for (int k = 1; k <= 9; k++) {
        long long cur = count_leq(x, k);
        res += 1LL * k * (cur - prev);
        prev = cur;
    }

    return res;
}

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

    for (int b = 1; b <= 10; b++) {
        pw[b][0] = 1;
        for (int i = 1; i < 20; i++) {
            pw[b][i] = pw[b][i - 1] * b;
        }
    }

    int T;
    cin >> T;

    while (T--) {
        long long L, R;
        cin >> L >> R;

        cout << F(R) - F(L - 1) << '\n';
    }
}