#include <bits/stdc++.h>
#define ll long long

using namespace std;

int main() {
    ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
    int t;
    cin >> t;
    while (t--) {
        string x,y;
        cin >> x >> y;
        ll ans=0;
        ll i=x.size()+1;
        while (i<y.size()) {
            if (i%2==1) {
                ans+=(ll)pow(10,i-1)*9;
            }
            i++;
        }
        if (x.size()%2==1) {
            string s(x.size(), '9');
            ans+= min(stoi(y),stoi(s))-stoi(x)+1;
        }
        if (y.size()%2==1&&y.size()!=x.size()) {
            string s(y.size()-1, '9');
            ans+= stoi(y)-stoi(s);
        }
        cout << ans << endl;
    }
    return 0;
}