#include <iostream>
using namespace std;
int main(){
long long q;
cin>>q;
while (q--)
{
long long l,r;
cin>>l>>r;
long long batas_awal=l,batas_akhir=r;
if(l%9!=1){
batas_awal=((l/9)*9)+1;
if(l%9==0){
batas_awal=l-8;
}
}
if(r%9!=0){
batas_akhir=((r/9)+1)*9;
}
long long suma=(batas_akhir-batas_awal+1)/9;
suma*=45;
long long sumb=0;
long long counter=1;
for (long long i = batas_awal; i <l ; i++)
{
sumb+=counter;
counter++;
}
counter=9;
long long sumc=0;
for (long long i = batas_akhir; i > r ; i--)
{
sumc+=counter;
counter--;
}
cout<<suma-sumb-sumc<<endl;
}
}
