Programming Articles - Page 2163 of 3363

IntPredicate interface is a built-in functional interface defined in java.util.function package. This functional interface accepts one int-valued argument as input and produces a boolean value as an output. This interface is a specialization of the Predicate interface and used as an assignment target for a lambda expression or method reference. It provides only one abstract method, test ().Syntax@FunctionalInterface public interface IntPredicate {  boolean test(int value); }Example for Lambda Expressionimport java.util.function.IntPredicate; public class IntPredicateLambdaTest {    public static void main(String[] args) {       IntPredicate intPredicate = (int input) -> {   // lambda expression          if(input == 100) {     ... Read More

This character class \p{javaLowerCase} matches lower case letters. This class matches the characters which returns true when passed as a parameter to the isLowerCase() method of the java.lang.Character class.Example 1 Live Demoimport java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main(String args[]) {       //Reading String from user       System.out.println("Enter a string");       Scanner sc = new Scanner(System.in);       String input = sc.nextLine();       //Regular expression       String regex = "[\p{javaLowerCase}]";       //Compiling the regular expression       Pattern pattern = ... Read More

This class matches white space characters. i.e. \t, , \x, 0B, \f, \r.Example 1 Live Demoimport java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class SpaceCharacters {    public static void main(String args[]) {       //Reading String from user       System.out.println("Enter a string");       Scanner sc = new Scanner(System.in);       String input = sc.nextLine();       //Regular expression       String regex = "[\p{Space}]";       //Compiling the regular expression       Pattern pattern = Pattern.compile(regex);       //Retrieving the matcher object       Matcher matcher = pattern.matcher(input);   ... Read More

This class matches hexa-decimal characters i.e. [0-9a-fA-F].Example 1 Live Demoimport java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class SpaceCharacters {    public static void main(String args[]) {       //Reading String from user       System.out.println("Enter a string");       Scanner sc = new Scanner(System.in);       String input = sc.nextLine();       //Regular expression       String regex = "[\p{XDigit}]";       //Compiling the regular expression       Pattern pattern = Pattern.compile(regex);       //Retrieving the matcher object       Matcher matcher = pattern.matcher(input);       int count = 0; ... Read More

If you want to specify the number of occurrences while constructing a regular expression you can use quantifiers. Java supports three types of quantifiers namely: greedy quantifiers, reluctant quantifiers and possessive quantifiers.Greedy quantifiers − Greedy quantifiers are the default quantifiers. A greedy quantifier matches as much as possible from the input string (longest match possible) if match not occurred it leaves the last character and matches again.Exampleimport java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Test {    public static void main(String[] args) {       Scanner sc = new Scanner(System.in);       System.out.println("Enter input text: ");     ... Read More

This class matches all the printable characters.Example 1 Live Demoimport java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class PrintableCharacters {    public static void main(String args[]) {       //Reading String from user       System.out.println("Enter a string");       Scanner sc = new Scanner(System.in);       String input = sc.nextLine();       //Regular expression       String regex = "[\p{Print}]";       //Compiling the regular expression       Pattern pattern = Pattern.compile(regex);       //Retrieving the matcher object       Matcher matcher = pattern.matcher(input);       int count = 0; ... Read More

This class matches all visible characters i.e. alphabets, digits, punctuation marks.Example 1 Live Demoimport java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class VisiblieCharacters {    public static void main(String args[]) {       //Reading String from user       System.out.println("Enter a string");       Scanner sc = new Scanner(System.in);       String input = sc.nextLine();       //Regular expression       String regex = "[\p{Graph}]";       //Compiling the regular expression       Pattern pattern = Pattern.compile(regex);       //Retrieving the matcher object       Matcher matcher = pattern.matcher(input);       ... Read More

Suppose we have an array that represents elements of arithmetic progression in order. One element is missing. We have to find the missing element. So if arr = [2, 4, 8, 10, 12, 14], output is 6, as 6 is missing.Using binary search, we can solve this problem. We will go to the middle element, then check whether the difference between the middle and next to the middle is the same as diff or not. If not, then the missing element is present between indices mid and mid + 1. If the middle element is the n/2th element in the ... Read More

Suppose we have a date (day, month and year). From this date, we have to find the day of the week of that given date. To solve this we will use Zeller’s Algorithm. The formula to find weekday using Zeller’s Algorithm is here𝑤=$$\lgroup d+\lfloor \frac{13(m+1)}{5} \rfloor+y+\lfloor\frac{y}{4} \rfloor+\lfloor\frac{c}{4} \rfloor+5c \rgroup mod 7$$The formula is containing some variables; They are −d − The day of the date.m − It is the month code. For March to December, it is 3 to 12, for January it is 13, and for February it is 14. When we consider January or February, then the given ... Read More

Suppose we have a value n, we have to generate n-th Tribonacci number. The Tribonacci numbers are similar to the Fibonacci numbers, but here we are generating a term by adding three previous terms. Suppose we want to generate T(n), then the formula will be like below −T(n) = T(n - 1) + T(n - 2) + T(n - 3)The first few numbers to start, are {0, 1, 1}We can solve them by following this algorithm −Algorithm• first := 0, second := 1, third := 1 • for i in range n – 3, do    o next := first ... Read More