spoj#FP. Finding password
Finding password
Bom has a list of n favorite numbers which are birthday, driving license, passport number, etc After creating an email account, Bom wants to choose a password as the largest number P among all possible numbers generated by the combinations of k (1 <= k <= n) positive numbers in the favorite list so that P is divisible by 9.
Your task is writing a program to help find P the password for Bom’s email.
Input
The first line contains a positive integer T as the number of test cases in the input file. The
following lines describe information of each test case including:
• One line containing two positive integers n and k,
• n following lines are n favorite numbers.
Output
The output file contains T lines; each line is the solution of the corresponding test case that is
either password P or -1 in case of not finding a feasible number.
Limits
T <= 30
1 <= k <= n <= 100
1 <= all favorite numbers <= 10^6
Sample input
2
3 2
1
2
3
5 2
1
2
3
4
5
Sample output
-1
54