#include<cstring>
#include<cstdio>
#include<algorithm>
#include<iostream>
#include<cstdlib>
#define ll long long

using namespace std;

int n;

ll dp[20][20];
int num[20];
ll a,b;

ll dfs(int i,int mod,bool e) {
    if(i<=0)return mod?0:1;
    if(!e&&dp[i][mod]!=-1)return dp[i][mod];
    ll res=0;
    int u=e?num[i]:9;
    for(int d=0; d<=u; d++) {
        int Mod=(mod+d)%10;
        res+=dfs(i-1,Mod,e&&d==u);
    }
    return e?res:dp[i][mod]=res;
}

ll solve(ll x) {
    int len=1;
    ll k=x;
    while(k) {
        num[len++]=k%10;
        k/=10;
    }
    num[len]=0;
    return dfs(len-1,0,1);
}

int main() {
    //freopen("test.in","r",stdin);
    int t;
    memset(dp,-1,sizeof dp);
    cin>>t;
    int ca=1;
    while(t--) {
        scanf("%I64d%I64d",&a,&b);
        printf("Case #%d: %I64d\n",ca++,solve(b)-solve(a-1));
    }
    return 0;
}

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