GoLang permutations calculator

permutations.go

// Permutation generator in Golang (array of strings)
package main

import (
	"fmt"
	"strings"
)

func nextPerm(p []int) {
    for i := len(p) - 1; i >= 0; i-- {
        if i == 0 || p[i] < len(p)-i-1 {
            p[i]++
            return
        }
        p[i] = 0
    }
}

func getPerm(orig, p []int) []int {
    result := append([]int{}, orig...)
    for i, v := range p {
        result[i], result[i+v] = result[i+v], result[i]
    }
    return result
}
  
func main() {
	// Init
	// Define array size and keys
	keys := []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}
	// Define seed words to permutate
	seed_values := []string{"word1", "word2", "word3", "word4", "word5", "word6", "word7", "word8", "word9", "word10", "word11", "word12"}
	// Worker
	for p := make([]int, len(keys)); p[0] < len(p); nextPerm(p) {
		_currentPermsMap := getPerm(keys, p)
		var res []string
		for i := range _currentPermsMap {
			key_shift := (_currentPermsMap[i] - 1)
			resulter := seed_values[key_shift]
			res = append(res, resulter)
		}
		fmt.Println(strings.Join(res, " "))
	}
	fmt.Println("Finished!")
}