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Please if you cross-post your question, tell all threads about the cross-post. Not informing us is not being fair to us as you then force us to duplicate answers that have already been given. We are...

Either a for loop (you know the size of the ArrayList, of course), or a for-each loop would work well here.

Nested for loops come to mind:
1 for loop to iterate through the Map
the inner one to iterate through each ArrayList.

Inside the nested for loop fill up another Map<String, Integer> to associate...