import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.Multimap;
 
public class Main {
    public static void main(String[] args) {
        Multimap<String, Integer> multimap = ArrayListMultimap.create();
 
        multimap.put("a", 1);
        multimap.put("a", 2);
 
        // Remove all elements associated with key "a"
        multimap.removeAll("a");
 
        // Check if the key "a" is still present
        System.out.println("Contains key 'a': " + multimap.containsKey("a"));
    }
}

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