Tree from nesting levels: Difference between revisions

=={{header|Go}}==

{{trans|Python}}

This is based on the Python recursive version.

<lang go>package main

import "fmt"

type any = interface{}

func toTree(list []int, index, depth int) (int, []any) {

var soFar []any

for index < len(list) {

t := list[index]

if t == depth {

soFar = append(soFar, t)

} else if t > depth {

var deeper []any

index, deeper = toTree(list, index, depth+1)

soFar = append(soFar, deeper)

} else {

index = index - 1

break

}

index = index + 1

}

if depth > 1 {

return index, soFar

}

return -1, soFar

}

func main() {

tests := [][]int{

{},

{1, 2, 4},

{3, 1, 3, 1},

{1, 2, 3, 1},

{3, 2, 1, 3},

{3, 3, 3, 1, 1, 3, 3, 3},

}

for _, test := range tests {

_, nest := toTree(test, 0, 1)

fmt.Printf("%17s => %v\n", fmt.Sprintf("%v", test), nest)

}

}</lang>

{{out}}

<pre>

[] => []

[1 2 4] => [1 [2 [[4]]]]

[3 1 3 1] => [[[3]] 1 [[3]] 1]

[1 2 3 1] => [1 [2 [3]] 1]

[3 2 1 3] => [[[3] 2] 1 [[3]]]

[3 3 3 1 1 3 3 3] => [[[3 3 3]] 1 1 [[3 3 3]]]

</pre>