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Golang program for implementation of Comb Sort

The Comb Sort is a variant of the Bubble Sort. Bubble sort always compares adjacent values. So all inversions are removed one by one. Comb Sort improves on Bubble Sort by using gap of size more than 1. The gap starts with a large value and shrinks by a factor of 1.3 in every iteration until it reaches the value 1. Thus Comb Sort removes more than one inversion counts with one swap and performs better than Bubble Sort.
// Comb Sort in Golang
package main

import (
	"fmt"
	"math/rand"
	"time"
)

func main() {

	slice := generateSlice(20)
	fmt.Println("\n--- Unsorted --- \n\n", slice)
	combsort(slice)
	fmt.Println("\n--- Sorted ---\n\n", slice, "\n")
}

// Generates a slice of size, size filled with random numbers
func generateSlice(size int) []int {

	slice := make([]int, size, size)
	rand.Seed(time.Now().UnixNano())
	for i := 0; i < size; i++ {
		slice[i] = rand.Intn(999) - rand.Intn(999)
	}
	return slice
}
 
func combsort(items []int) {
	var (
		n = len(items)
		gap = len(items)
		shrink = 1.3
		swapped = true
	)
	
	for swapped {
		swapped = false
        	gap = int(float64(gap) / shrink)
        	if gap < 1 {
			gap = 1
		}
		for i := 0; i+gap < n; i++ {
			if items[i] > items[i+gap] {
				items[i+gap], items[i] = items[i], items[i+gap]
				swapped = true
			}	
		}
	}
}
C:\golang\time>go run s2.go

--- Unsorted ---

[-317 -381 -14 -215 -590 -243 -412 380 -312 925 158 -46 177 22 -482 273 217 514 -392 424]

--- Sorted ---

[-590 -482 -412 -392 -381 -317 -312 -243 -215 -46 -14 22 158 177 217 273 380 424 514 925]


C:\golang\time>