#248 PECS: Reading from and Writing to Generic Collections

Companies:

Alfa-Bank

Themes:

JavaCollections & GenericsPractice

Which methods do not cause a compilation error?

public class Main {

    public static void main(String[] args) {

    }

    public static <T> T getFirst(List<? super T> list) {
        return list.get(0);
    }

    public static <T> T getFirst(List<? extends T> list) {
        return list.get(0);
    }

    public static <T> void putLast(List<? super T> list, T t) {
        return list.add(t);
    }

    public static <T> void putLast(List<? extends T> list, T t) {
        return list.add(t);
    }
}

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