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package com.mycompany.ex23;

import java.util.Collection;
import java.util.Map;

public class Main2 {
    // 
    public static void main(String[] args) {        
        String s = null; 
        // 1) Collection 
        Collection<String> l = null;          
        // Collection<int> li = null;
        // int     Integer
        // double  Double
        // long    Long
        // boolean Boolean
        // char    Character
        Collection<Integer> li = null;
        // 
        Map<String, String>  map1;
        Map<Integer, String> map2;
       
    }
}