Question

How to use HashMap in Java

Answer 1

import java.util.HashMap;

public class MyClass {
    public static void main(String args[]) {
        HashMap<String, Integer> hashmap = new HashMap<>();

        hashmap.put("java", 1);
        hashmap.put("c", 2);
        hashmap.put("c++", 3);
        hashmap.put("python", 4);

        System.out.println(hashmap);
        System.out.println(hashmap.get("java"));
        System.out.println(hashmap.get("php"));
    }
}



/*
run:

{c++=3, python=4, java=1, c=2}
1
null

*/

 

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