Could someone give me a tip on why my code is getting "Memory limit exceeded"?

Problem: http://mirror.codeforces.com/contest/588/problem/E

Here's my code: http://mirror.codeforces.com/contest/588/submission/13655996

I tried to make a LCA table of sets (with size less than 10) and for each query I merge the ranges getting the 'a' minimums.