public class Program
{
    public static int[] what(int[] arr, int k)
    {
        int n = arr.length;
        int[] b = new int[n];
        int[] c = new int[k+1];
        for (int i=0; i<k+1; i++) c[i]=0;
        for (int j=0; j <n; j++) c[arr[j]]=c[arr[j]]+1; //*
        for (int i=1; i <k+1; i++) c[i] = c[i] + c[i-1]; //**
        for (int j=n-1; j >= 0; j--) //***
        {
            b[c[arr[j]]-1]=arr[j];
            c[arr[j]]=c[arr[j]]-1;
        }
        return b;
    }
    public static void main(String[] args)
    {
        int[] arr = new int[] {5,0,2,1,3,0,5};
        arr = what(arr,5);
        for (int i=0; i < arr.length; i++) System.out.println(arr[i]);
    }
}