Hackerrank Ruby Array - Index, Part 1 Solution

Hackerrank Ruby Array - Index, Part 1 Solution

.MathJax_SVG_Display {text-align: center; margin: 1em 0em; position: relative; display: block!important; text-indent: 0; max-width: none; max-height: none; min-width: 0; min-height: 0; width: 100%} .MathJax_SVG .MJX-monospace {font-family: monospace} .MathJax_SVG .MJX-sans-serif {font-family: sans-serif} .MathJax_SVG {display: inline; font-style: normal; font-weight: normal; line-height: normal; font-size: 100%; font-size-adjust: none; text-indent: 0; text-align: left; text-transform: none; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0; min-height: 0; border: 0; padding: 0; margin: 0} .MathJax_SVG * {transition: none; -webkit-transition: none; -moz-transition: none; -ms-transition: none; -o-transition: none} .mjx-svg-href {fill: blue; stroke: blue}

Array collections offer various ways to access their elements.

The positions are 0 indexed. Objects of the array can be accessed using the [] method which may take various arguments, as explained below.  arr = [9, 5, 1, 2, 3, 4, 0, -1]

  • A number which is the position of element>>arr[4] => 3

or>>arr.at(4) => 3

  • A range indicating the start and the end position >>arr[1..3] # .. indicates both indices are inclusive. => [5,1,2] >>arr[1...3] # ... indicates the last index is excluded. => [5,1]
  • Start index and the length of the range>>arr[1,4] => [5, 1, 2, 3]

For this challenge, your task is to complete the functions using syntax as explained above.

Solution in ruby

Approach 1.

def element_at(arr, index)
    arr[index]
end

def inclusive_range(arr, start_pos, end_pos)
    arr[start_pos..end_pos]
end

def non_inclusive_range(arr, start_pos, end_pos)
    arr[start_pos...end_pos]
end

def start_and_length(arr, start_pos, length)
    arr[start_pos, length]
end

Approach 2.

def element_at(arr, index)
    # return the element of the Array variable `arr` at the position `index`
    
     arr[index]
end

def inclusive_range(arr, start_pos, end_pos)
    # return the elements of the Array variable `arr` between the start_pos and end_pos (both inclusive)
    arr[start_pos..end_pos]
end

def non_inclusive_range(arr, start_pos, end_pos)
    # return the elements of the Array variable `arr`, start_pos inclusive and end_pos exclusive
    arr[start_pos...end_pos]
end

def start_and_length(arr, start_pos, length)
    # return `length` elements of the Array variable `arr` starting from `start_pos`
    arr[start_pos, length]
end

Approach 3.

def element_at(arr, index)
    # return the element of the Array variable `arr` at the position `index`
    # arr.at(index) # or
    arr[index]
end

def inclusive_range(arr, start_pos, end_pos)
    # return the elements of the Array variable `arr` between the start_pos and end_pos (both inclusive)
    arr[start_pos..end_pos]
end

def non_inclusive_range(arr, start_pos, end_pos)
    # return the elements of the Array variable `arr`, start_pos inclusive and end_pos exclusive
    arr[start_pos...end_pos]
end

def start_and_length(arr, start_pos, length)
    # return `length` elements of the Array variable `arr` starting from `start_pos`
    arr[start_pos,length]
end

Subscribe to The Poor Coder | Algorithm Solutions

Don’t miss out on the latest issues. Sign up now to get access to the library of members-only issues.
[email protected]
Subscribe