#include <bits/stdc++.h>
using namespace std;
template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl
using ll = long long;
const int maxn = 1e6 + 5;
int f(ll x) {
if (x<10) return x;
int sum = 0;
while (x>0) {
sum += x%10;
x /= 10;
}
return f(sum);
}
ll solve(ll x) {
if (x==0) return 0;
//1,2,3,4..9,1,2...
ll x0 = x/9*9 + 1;
ll s9 = 0;
for (int i=1; i<=9; i++) s9+=i;
ll res= 1ll*(x/9)*s9;
for (int i=1; i<=9 && x0<=x; i++,x0++) {
res+=i;
}
return res;
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
int t;
cin>>t;
while (t--) {
ll l,r;
cin>>l>>r;
ll res = solve(r) - solve(l-1);
cout<<res<<"\n";
}
return 0;
}
