CountingSort.go

package main
import "fmt"

const MaxUint = ^uint(0)
const MaxInt = int(MaxUint >> 1)
const MinInt = - MaxInt - 1

func countingSort(list []int) {
    maxNumber := MinInt
    minNumber := MaxInt
    for _, v := range list {
        if v > maxNumber {
            maxNumber = v
        }
        if v < minNumber {
            minNumber = v
        }
    }

    count := make([]int, maxNumber - minNumber + 1)

    for _, x := range list {
        count[x - minNumber]++
    }
    index := 0
    for i, c := range count {
        for ; c > 0; c-- {
            list[index] = i + minNumber
            index++
        }
    }
}

func main() {
    var x int
    fmt.Printf("Enter the size of the array : ")
    fmt.Scan(&x)
    fmt.Printf("Enter the elements of the array : ")
    a := make([]int, x)
    for i := 0; i < x; i++ {
        fmt.Scan(&a[i])
    }
    list := a    // A copy of the array 'a' is assigned to 'list' 
    fmt.Println("before sorting", list)
    countingSort(list)
    fmt.Println("after sorting", list)
}

/*
Sample Input :
    Enter the size of the array : 4                                                                                              
    Enter the elements of the array : 12 29 10 78
Sample Output :
    After sorting [10 12 29 78]	
*/