hdu4507

#include <cmath>
#include <cstdio>
#include <cstring>
#define LL long long
#define MOD 1000000007LL
using namespace std;

LL dp1[20][10][7][7][2];
LL dp2[20][10][7][7][2];
LL cnt[20][10][7][7][2];

LL a[20],b[20],c[20];
LL B,C;
LL m10 (LL x) {
LL t = 1;
for(;x;--x)
t = t * 10 % MOD;
return t;
}
void dfs (LL u,LL la,LL mods,LL smds,LL lim) {
if(u == 0) {
dp1[u][la][mods][smds][lim] = 0;
dp2[u][la][mods][smds][lim] = 0;
cnt[u][la][mods][smds][lim] = 0;
if(mods != 0 && smds != 0) {
cnt[u][la][mods][smds][lim]++;
}
return;
}
if(cnt[u][la][mods][smds][lim] != -1) {
return;
}
cnt[u][la][mods][smds][lim] = 0;
dp1[u][la][mods][smds][lim] = 0;
dp2[u][la][mods][smds][lim] = 0;
LL ed = lim ? a[u] : 9LL;

for(LL i = 0;i <= ed;++i) {
if(i == 7LL)
continue;
int d = lim && i == a[u];
dfs(u - 1,i,(mods * 10 + i) % 7,(smds + i) % 7,d);

cnt[u][la][mods][smds][lim] = (cnt[u][la][mods][smds][lim] + cnt[u - 1][i][(mods * 10 + i) % 7][(smds + i) % 7][d]) % MOD;
dp1[u][la][mods][smds][lim] = (dp1[u][la][mods][smds][lim] + (cnt[u - 1][i][(mods * 10 + i) % 7][(smds + i) % 7][d] * i * m10(u - 1)) % MOD + dp1[u - 1][i][(mods * 10 + i) % 7][(smds + i) % 7][d]) % MOD;
dp2[u][la][mods][smds][lim] = (dp2[u][la][mods][smds][lim] + (((cnt[u - 1][i][(mods * 10 + i) % 7][(smds + i) % 7][d] * i * i)%MOD * (m10(2 * u - 2) % MOD)) % MOD + (2 * i * m10(u - 1) %MOD * dp1[u - 1][i][(mods * 10 + i) % 7][(smds + i) % 7][d]) % MOD + dp2[u - 1][i][(mods * 10 + i) % 7][(smds + i) % 7][d])) % MOD;
}
return ;

}

int main () {

int T;
scanf("%d",&T);

while(T--) {
memset(dp1,-1,sizeof dp1);
memset(dp2,-1,sizeof dp2);
memset(cnt,-1,sizeof cnt);

scanf("%I64d %I64d",&B,&C);
--B;

LL lb = log10(B) + 1;
LL bb = B;
for(LL i = 1;B;++i) {
b[i] = B % 10;
B /= 10;
}

LL lc = log10(C) + 1;
for(LL i = 1;C;++i) {
c[i] = C % 10;
C /= 10;
}

LL t1;
if(bb) {
for(LL i = 1;i <= lb;++i) {
a[i] = b[i];
}
dfs(lb,0,0,0,1);
t1 = dp2[lb][0][0][0][1];
}
else t1 = 0;
memset(dp1,-1,sizeof dp1);
memset(dp2,-1,sizeof dp2);
memset(cnt,-1,sizeof cnt);
for(LL i = 1;i <= lc;++i) {
a[i] = c[i];
}
dfs(lc,0,0,0,1);
LL t2 = dp2[lc][0][0][0][1];
printf("%I64d\n",(t2 - t1 < 0) ? (t2 - t1 + MOD) : (t2 - t1));
}
}