Which problems did you find the most interesting and creative in the previous year. Feel free to mention here. 
And also tell which problem, you think, deserves to be the best problem of the year, from your point of view. 
program to find a 10-digit number which when devided by its length is divisible.
so, if we take the 0th index it must be devisible by 1, if we take [0,1] it should be devisible by 2, similarly if we take [0,2] it should be divisible by 3 and on till the end which should be devisible by 10.