数学上的一个大数计算的问题的算法构成,采用C语言的程序的设计的办法怎么做

Problem Description
Xiao Jun likes math and he has a serious math question for you to finish.

Define F[x] to the xor sum of all digits of x under the decimal system,for example F(1234) = 1 xor 2 xor 3 xor 4 = 4.

Two numbers a,b(a≤b) are given,figure out the answer of F[a] + F[a+1] + F[a+2]+…+ F[b−2] + F[b−1] + F[b] doing a modulo 109+7.

Input
The first line of the input is a single integer T(T<26), indicating the number of testcases.

Then T testcases follow.In each testcase print three lines :

The first line contains one integers a.

The second line contains one integers b.
1≤|a|,|b|≤100001,|a| means the length of a.

Output
For each test case, output one line "Case #x: y", where x is the case number (starting from 1) and y is the answer.

Sample Input
4
0
1
2
2
1
10
9999
99999

Sample Output
Case #1: 1
Case #2: 2
Case #3: 46
Case #4: 649032