Hello I wanted to know how can this java code can be improved. Currently it get TLE in few test cases.It would be helpful if someone can find the bottleneck in this solution.

Problem: https://cses.fi/problemset/task/1192
Solution: find the number of connected components.

code link: https://cses.fi/paste/b4d685acb261aaca26c573/

equivalent code in c++ is 10 times faster than java.

I am trying to switch to java for cp.