Putting the same key twice in a Map

Predict the outputEasyJava only

Main.java

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Map<String, Integer> map = new HashMap<>();
        System.out.println(map.put("a", 1));
        System.out.println(map.put("a", 2));
        System.out.println(map.get("a") + " " + map.size());
        System.out.println(map.get("b"));
    }
}

What does it print?

Graded by exact match. Spaces at the ends of lines and blank lines at the end do not count.

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