#include<cstdio>
#include<iostream>
#include<string>
#include<sstream>
using namespace std;
stringstream ss;
int yu,l,r,n;
string s,t;
int main()
{
    freopen("xiaokai.in","r",stdin);
    freopen("xiaokai.out","w",stdout);
    scanf("%d",&n);
    while(n--)
    {
    scanf("%d%d",&l,&r);
    s="";
    yu=0;
    for(int i=l;i<=r;i++)
    {
        t="";
        ss<<i;
        ss>>t;
        ss.clear();
        s=s+t;
    }
    int ans=0,t;
    for(int i=0;i<s.size();i++)
    {
        t=(s[i]-'0'+yu*10)/9+'0';
        yu=(s[i]-'0'+yu*10)%9;
        s[i]=t;
    }    
    cout<<yu<<endl;
    }
    
    return 0;
}