Write an integer number below one million in words. Human languages have many inconsistencies, especially in the most frequent constructs. Spelling numbers seems to be a simple task, but due to a number of small differences, the resulting program is quite big. The program is listed on the next page. Let’s discuss the algorithm first. … Continue reading “📘 Spelling numbers using Perl 6”

# Category: Chapter 2. Numbers

## 📘 Convert to Roman numerals using Perl 6

Convert an integer number to a Roman numerals string. Roman numbers are not a direct translation of the decimal system. In this task, we assume that the number is not morethan 3999, which is the maximum a regular Roman number can reach. Let’s use the algorithm that keeps the table of pre-calculated sequences of Roman letters … Continue reading “📘 Convert to Roman numerals using Perl 6”

## 📘 Compose the largest number using Perl 6

Given the list of integers, compose the largest possible number by concatenating them. This task requires working with the same data as with numbers and strings. To compose the largest possible number out of a list of integers, we need to reorder them so that the largest numbers come first. The easiest way to achieve … Continue reading “📘 Compose the largest number using Perl 6”

## 📘 Bit counter written in Perl 6

Count the number of bits set to 1 in a binary representation of a positive integer number. There are two approaches to this task: either treat the binary sequence as a string or count real bits in the machine representation of the number. In Perl, both approaches are fine. We restrict ourselves to the positive … Continue reading “📘 Bit counter written in Perl 6”

## 📘 Computing the sum of digits using Perl 6

Calculate the sum of digits of a given number. The solution of this task is based on the splitmethod that you can call on any object that is convertible to strings. The following code takes an integer number and splits it into separate characters, one per digit. Then the reduction operator adds up all the digits, … Continue reading “📘 Computing the sum of digits using Perl 6”

## 📘 Presenting integers as binary, octal, and hex using Perl 6

Print a given integer number in the binary, octal, and hexadecimal representations. On an integer object, call the basemethod with the corresponding number: say 42.base(2); # 101010say 42.base(8); # 52say 42.base(16); # 2A Alternatively, use the fmt method, which is defined for integers and accepts the formatting string in the printfformat: my $int = 42;say $int.fmt(‘Hex: %x’); # Hex: 2asay $int.fmt(‘Oct: %o’); # … Continue reading “📘 Presenting integers as binary, octal, and hex using Perl 6”

## 📘 Converting binary to integer using Perl 6

Convert a binary number to a decimal integer. Perl is good at its ease of switching between numerical and string representation of the same data. This task is an example where this feature can be used. The idea is to take a binary number, treat it as a string, prepend the 0bprefix indicating the binary value, … Continue reading “📘 Converting binary to integer using Perl 6”

## 📘 ‘Guess the number’ in Perl 6

Write a program that generates a random integer number 0 through 10 and asks the user to guess it, saying if the entered value is too small or too big. First, a random number needs to be generated. In Perl 6, the randroutine can be called on an integer object, and it returns a random floating-point … Continue reading “📘 ‘Guess the number’ in Perl 6”

## 📘 All Unicode digits in Perl 6

Print all Unicode digits. Perl 6 has the best support of Unicode among the modern programming languages. When talking about digits, it is worth remembering that the Unicode standard marks as digits much more than the regular ten characters used in English, for example. Let us iterate over the whole range of codepoints and select … Continue reading “📘 All Unicode digits in Perl 6”

## 📘 Implementing the Monte Carlo method using Perl 6

Calculate the area of a circle and the volume of a sphere of radius 1 using the Monte Carlo method. The Monte Carlo method is a statistical method of calculating data whose formula is not known. The idea is to generate a big number of random numbers and see how many of them satisfy the … Continue reading “📘 Implementing the Monte Carlo method using Perl 6”