Pass adjList as well by reference. Passing it as value creates memory each time the function is called. https://stackoverflow.com/questions/26647152/passing-vectors-to-a-function-value-vs-reference-

But still it gives you TLE 54543465. Try to optimise your dfs.

Kavi1234 is right about reference. The problem is that you find the answer for user separately from the beginning, which gives TLE. Note that answers for users in the same component are the same.

A link that may help: https://www.geeksforgeeks.org/union-find/