Java 13 has been released a few days ago. Here are some changes that may be useful for competitive programming.

• Switch expressions: first introduced in Java 12. In Java 13, a value is returned from a switch expression using yield statement:

String numType = switch (num) {
	0 -> "zero";
	1 -> "one";
	default -> {
		for (int i = 2; i < num; i++) {
			if (num % i == 0) {
				yield "composite";
			}
		}
		yield "prime";
	}
};

• Text blocks: multi-line string literals, similar to Python:

String input = """
	3 3
	1 2
	1 3
	2 3""";

If you know about other useful features, post it here.

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