#266 HashMap Behavior with Key Collisions

Companies:

Aston

Themes:

JavaCollections & GenericsCode Review

What will be printed?

import java.util.*;

class Main {
    private int i;

    public Main(int i) {
        this.i = i;
    }

    public static void main(String[] args) {
        Map<Main, Object> map = new HashMap<>();
        map.put(new Main(1), null);
        map.put(new Main(2), null);
        map.put(new Main(1), null);
        System.out.println(map.size());
    }

    @Override
    public boolean equals(Object o) {
        return super.equals(o);
    }

    @Override
    public int hashCode() {
        return -1;
    }
}

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