## Hackerrank Ruby Array - Index, Part 1 Solution

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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
```