Toistot

#include <algorithm>
#include <array>
#include <iostream>
#include <climits>
#include <cmath>
#include <iomanip>
#include <map>
#include <set>
#include <vector>

using namespace std;

using Z = long long int;

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

    vector<Z> all;
    for(Z len = 1, start = 1, end = 10; len <= 4; ++len, start *= 10, end *= 10) {
        Z repCoef = 1;
        for(Z rep = 2; rep * len <= 9; ++rep) {
            repCoef = end * repCoef + 1;
            for(Z pattern = start; pattern < end; ++pattern) {
                Z val = repCoef * pattern;
                all.push_back(val);
            }
        }
    }

    sort(all.begin(), all.end());
    all.erase(unique(all.begin(), all.end()), all.end());

    Z tc;
    cin >> tc;

    for(Z ti = 0; ti < tc; ++ti) {
        Z a, b;
        cin >> a >> b;

        cout << upper_bound(all.begin(), all.end(), b) - lower_bound(all.begin(), all.end(), a) << "\n";
    }

    return 0;
}

Test 1

Group: 1, 2, 3, 4

Verdict: ACCEPTED

Test 2

Group: 2, 3, 4

Verdict: ACCEPTED

Test 3

Group: 3, 4

Verdict: ACCEPTED

Test 4

Group: 4

Verdict: WRONG ANSWER

Test 5

Group: 1, 2, 3, 4

Verdict: ACCEPTED

Test 6

Group: 4

Verdict: WRONG ANSWER