#include<bits/stdc++.h>
using namespace std;
inline int read(){
    int ans=0,sgn=1;
    char ch=getchar();
    while(!isdigit(ch)){
   	if (ch=='-')sgn=-1;
   	ch=getchar();
    }
    while(isdigit(ch))ans=(ans<<3)+(ans<<1)+(ch^48),ch=getchar();    
    return ans*sgn;
}
typedef unsigned long long ULL;
int pow10[10];
int len(int n)
{
    int ans=0;
    while(n!=0)
    {
        ans++;
        n/=10;
    }
    return ans;
}
int main()
{
    freopen("xiaokai.in","r",stdin);
    freopen("xiaokai.out","w",stdout);
    int q,l,r;q=read();
    pow10[0]=1;
    for(int i=1;i<=10;i++)
    {
        pow10[i]=pow10[i-1]*10;
    }
    for(int i=1;i<=q;i++)
    {
        l=read();r=read();
        ULL ans=0;
        for(int j=l;j<=r;j++)
        {
            ans*=pow10[len(j)];
            ans%=9;
            ans+=j;
            ans%=9;
        }
        cout<<ans<<endl;
    }
}