Variable-Sized-Arrays

** Input Format ** The first line contains two space-separated integers denoting the respective values of (the number of variable-length arrays) and (the number of queries). Each line of the subsequent lines contains a space-separated sequence in the format k a[i]0 a[i]1 … a[i]k-1 describing the -element array located at . Each of the subsequent lines contains two space-separated integers describing the respective values of (an index in array ) and (an index in the array referenced by ) for a query.