How to Use the Ruby downto Method

09/24/2021

Contents

In this article, you will learn how to use the Ruby downto method.

Using the downto Method

The downto method is a built-in method in the Ruby programming language. It is used to iterate downwards from a given number to a specified limit, performing a block of code at each step.

Syntax

The syntax for using the downto method is as follows:

start.downto(stop) do |variable|
  # Code to be executed
end

Parameters

  • start: The starting number.
  • stop: The stopping number.
  • variable: The variable used to represent the current iteration value.

Examples

Printing numbers from 10 to 1

10.downto(1) do |i|
  puts i
end

Output:

10
9
8
7
6
5
4
3
2
1

In the above example, we start at 10 and iterate downwards until we reach 1. At each step, we print the current value of the iterator variable i.

Summing up numbers from 1 to 10

sum = 0
10.downto(1) do |i|
  sum += i
end
puts sum

Output:

55

In the above example, we start at 10 and iterate downwards until we reach 1. At each step, we add the current value of the iterator variable i to the variable sum. After the loop has completed, we print the value of sum.

Using a range object with downto

(1..10).downto(1) do |i|
  puts i
end

Output:

10
9
8
7
6
5
4
3
2
1

In the above example, we use a range object (1..10) as the starting value for the downto method. This allows us to iterate over the range of values from 1 to 10 in a descending order.

#Ruby