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Function composition

Disjunct all

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It is time to learn how to perform operations on predicates, just like in mathematical logic!

Write the disjunctAll method that accepts a list of IntPredicate objects and returns a single IntPredicate. The result predicate is a disjunction of all input predicates.

Disjunction means that if any of the predicates would return true, the composed predicate should return true as well.

If the input list is empty, the resulted predicate must return false for any integer value (always false predicate).

Write a program in Java 17

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.Scanner;

import java.util.function.IntPredicate;

import java.util.stream.Collectors;

class CombiningPredicates {

/**

* The method represents a disjunct operator for a list of predicates.

* For an empty list it returns the always false predicate.

public static IntPredicate disjunctAll(List<IntPredicate> predicates) {

return n -> false; // write your code here

}

// Don't change the code below

public static void main(String[] args) {

Scanner scanner = new Scanner(System.in);

String[] strings = scanner.nextLine().split(" ");

List<Boolean> values = Arrays.stream(strings)

.map(Boolean::parseBoolean)

.collect(Collectors.toList());

List<IntPredicate> predicates = new ArrayList<>();

values.forEach(v -> predicates.add(x -> v));

System.out.println(disjunctAll(predicates).test(0));

}

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