How to find the Indices of All Occurrences of Substring in Ruby - Step by Step Examples

How to find the Indices of All Occurrences of Substring in Ruby ?

Answer

To find the indices of all occurrences of a substring in Ruby, you can use the each_index method with a block to iterate through the string and store the indices of matches.


✐ Examples

1 Find Indices of All Occurrences in String

In this example,

  1. We create a string variable str with a string value.
  2. We use the each_index method with a block to iterate through str and store the indices of matches.
  3. We print the indices of all occurrences.

Ruby Program

str = "Hello Hello Hello"
substr = "Hello"
indices = []
str.chars.each_index { |i|
    indices << i if str[i, substr.length] == substr
}
puts "Indices of all occurrences: #{indices}"

Output

Indices of all occurrences: [0, 6, 12]

2 Find Indices of All Occurrences in Another String

In this example,

  1. We create two string variables str and substr with different values.
  2. We use the each_index method with a block to iterate through str and store the indices of matches.
  3. We print the indices of all occurrences.

Ruby Program

str = "apple banana cherry banana"
substr = "banana"
indices = []
str.chars.each_index { |i|
    indices << i if str[i, substr.length] == substr
}
puts "Indices of all occurrences: #{indices}"

Output

Indices of all occurrences: [6, 20]

Summary

In this tutorial, we learned How to find the Indices of All Occurrences of Substring in Ruby language with well detailed examples.


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