Spiral Matrix

Traverse a 2D matrix in spiral order starting from the top-left corner.

Code

Algorithms

echo "$matrix" | jq 'def spiral: if length == 0 then [] else .[0] + ([.[1:][] | .[-1]] | if . == [[]] then [] else . end) + (if length > 1 then ([-1]|reverse) else [] end) + ([.[1:-1][] | .[0]] | reverse) + (.[1:-1] | map(.[1:-1]) | spiral) end; spiral'

Parameters

matrix(string)

2D matrix (JSON)

Server

More Bash Snippets

Array Difference

Find elements in the first array that are not present in the second array.

Array Frequencies

Count how many times each value appears in an array and return a frequency map.

Array Head

Get the first n elements of an array.

Array Intersection

Find common elements that exist in both arrays.

Array Tail

Get the last n elements of an array.

Array Union

Combine two arrays and remove duplicates to produce a union.