#include <bits/stdc++.h>
using namespace std;
#define int long long
#define faster ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int solve(int x){
while(x>9){
int tmp = x;
x = 0;
while(tmp>0){
x+=tmp%10;
tmp/=10;
}
}
return x;
}
signed main(){
faster
int q;
int ax, bx;
cin >> q;
while(q--){
int sum = 0;
cin >> ax >> bx;
if(ax>9) ax =solve(ax);
if(bx>9) bx = solve(bx);
if(ax<bx){
for(int i = ax; i <= bx; i++) sum+=i;
}
else if(ax>=bx){
for(int i = bx; i <= ax; i++) sum+=i;
}
cout << sum << endl;
}
}