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| #include<algorithm>
#include<bitset>
#include<complex>
#include<deque>
#include<exception>
#include<fstream>
#include<functional>
#include<iomanip>
#include<ios>
#include<iosfwd>
#include<iostream>
#include<istream>
#include<iterator>
#include<limits>
#include<list>
#include<locale>
#include<map>
#include<memory>
#include<new>
#include<numeric>
#include<ostream>
#include<queue>
#include<set>
#include<sstream>
#include<stack>
#include<stdexcept>
#include<streambuf>
#include<string>
#include<typeinfo>
#include<utility>
#include<valarray>
#include<vector>
#include<cctype>
#include<cerrno>
#include<cfloat>
#include<ciso646>
#include<climits>
#include<clocale>
#include<cmath>
#include<csetjmp>
#include<csignal>
#include<cstdarg>
#include<cstddef>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<ctime>
using namespace std;
#define re register
#define int long long
#define eps 1e-5
#define mod 1000000007
class Quick_Input_Output{
private:
static const int S=1<<21;
#define tc() (A==B&&(B=(A=Rd)+fread(Rd,1,S,stdin),A==B)?EOF:*A++)
char Rd[S],*A,*B;
#define pc putchar
public:
#undef gc
#define gc getchar
inline int read(){
int res=0,f=1;char ch=gc();
while(ch<'0'ch>'9'){if(ch=='-') f=-1;ch=gc();}
while(ch>='0'&&ch<='9') res=res*10+ch-'0',ch=gc();
return res*f;
}
inline void write(int x){
if(x<0) pc('-'),x=-x;
if(x<10) pc(x+'0');
else write(x/10),pc(x%10+'0');
}
#undef gc
#undef pc
}I;
#define File freopen("tmp.in","r",stdin);freopen("tmp.out","w",stdout);
int a[30],m,pw[30];
struct node{int ans,sum,sqrsum;}dp[30][10][10];
inline node DFS(int now,int presum,int prenum,int lim){
if(!now) return (node){presum!=0&&prenum!=0,0,0};
if(!lim&&~dp[now][presum][prenum].ans) return dp[now][presum][prenum];
re int Max=lim?a[now]:9;node ans=(node){0,0,0},bk;
for(int i=0;i<=Max;i++){
if(i==7) continue ;
bk=DFS(now-1,(presum+i)%7,(prenum*10+i)%7,lim&&i==Max);
ans.ans+=bk.ans;ans.ans%=mod;
ans.sum+=bk.sum;ans.sum%mod;
ans.sum+=pw[now-1]*i%mod*bk.ans%mod;ans.sum%=mod;
ans.sqrsum+=bk.sqrsum;ans.sqrsum%=mod;
ans.sqrsum+=2*pw[now-1]%mod*i%mod*bk.sum%mod;ans.sqrsum%=mod;
ans.sqrsum+=bk.ans*pw[now-1]%mod*pw[now-1]%mod*i%mod*i%mod;ans.sqrsum%=mod;
}
if(!lim) dp[now][presum][prenum]=ans;
return ans;
}
inline int solve(int N){
re int x=N;m=0;
while(x){
a[++m]=x%10;
x/=10;
}
for(int i=1;i<=28;i++)
for(int j=0;j<10;j++)
for(int k=0;k<10;k++) dp[i][j][k]=(node){-1,0,0};
return DFS(m,0,0,1).sqrsum;
}
int T,L,R;
signed main(){
pw[0]=1;for(int i=1;i<=28;i++) pw[i]=pw[i-1]*10,pw[i]%=mod;
T=I.read();
while(T--){
L=I.read();R=I.read();
I.write((solve(R)-solve(L-1)+mod)%mod);putchar('\n');
}
return 0;
}
|