1 #include "cstdio"
2 #include "math.h"
3 #include "cstring"
4 #define mod 1000000007LL
5 #define LL long long
6
7 struct node
8 {
9 LL cnt,sum,sqsum;
10 node() {cnt=-1;sum=sqsum=0;}
11 node(LL cnt,LL sum,LL sqsum):cnt(cnt),sum(sum),sqsum(sqsum) {}
12 }dp[20][10][10];
13
14 LL a[20],p[25];
15
16 node dfs(int pos,int re1,int re2,bool limit)
17 {
18 if(!pos) return re1!=0&&re2!=0?node(1,0,0):node(0,0,0);
19 if(!limit&&dp[pos][re1][re2].cnt!=-1) return dp[pos][re1][re2];
20 int up=limit?a[pos]:9;
21 node ans;ans.cnt = 0;
22 for(int i=0;i<=up;i++)
23 {
24 if(i==7) continue;
25 node next=dfs(pos-1,(re1+i)%7,(re2*10+i)%7,limit&&i==up);
26 ans.cnt+=next.cnt;
27 ans.cnt%=mod;
28 ans.sum+=(next.sum+((p[pos]*i)%mod)*next.cnt%mod)%mod;
29 ans.sum%=mod;
30 ans.sqsum+=(next.sqsum+((2*p[pos]*i)%mod)*next.sum)%mod;
31 ans.sqsum%=mod;
32 ans.sqsum+=((next.cnt*p[pos])%mod*p[pos]%mod*i*i%mod);
33 ans.sqsum%=mod;
34 }
35 if(!limit) dp[pos][re1][re2]=ans;
36 return ans;
37 }
38
39 LL f(LL x)
40 {
41 int pos=0;
42 while(x)
43 {
44 a[++pos]=x%10;
45 x/=10;
46 }
47 node tt=dfs(pos,0,0,true);
48 return tt.sqsum;
49 }
50
51 int main()
52 {
53 int T;
54 LL l,r;
55 scanf("%d",&T);
56 p[1]=1;
57 for(int i=2;i<=20;i++) p[i]=(p[i-1]*10)%mod;
58 while(T--)
59 {
60 scanf("%I64d%I64d",&l,&r);
61 LL ans=f(r);
62 ans-=f(l-1);
63 printf("%I64d\n",(ans%mod+mod)%mod);
64 }
65 }
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