#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#include "head1.h"
#define NMAX 20


int read_array(const char* name, double *a, int maxn)
{

    int i;
    FILE* fp;
    if(!(fp = (fopen(name,"r"))))return -1;
    for(i = 0; i < maxn; i++)
    {
        if(fscanf(fp, "%lf", a + i)!= 1)
        {
            if(feof(fp))
            {
                fclose(fp);
                return -2;
            }
            else{
                fclose(fp); return i;
                }
        }
    }
        fclose(fp);
        return i;
}
 void init_array(double *a, int n, int key)
 {
     int i;
     srand(key);

     for(i = 0; i < n; i++)
     a[i] = rand();
 }
 void print_array(double *a, int n)
 {
     int i;
     int m = (n > NMAX? NMAX:n);
     for(i = 0; i < m; i++)
         printf("%lf  ", a[i]);

 }

void merge(double *a, double *c, int left, int right)
 {
     int i = 0;
     int j = 0;
     int middle = (left + right) / 2;
     c = a;
     while((i + j) < (right - left)){
        if(a[left + i] <= a[middle + j]){
            c[left + i + j] = a[left + i];
            if(i < (middle - left)){i++;}
        }else{
            c[left + j + i] = a[middle + j];
            if(j < (right - middle)){j++;}
        }
     }
     a = c;
 }

void sort(double *a,  double* c, int n)
 {
     int k = 2;
     int j;
     while((1 >> k) < n)
     {

	for(j = 0; j < (n /  k); j++)
	{
		merge(a, c, k * j, k * (j + 1));
	}
	if (((n / k) * k) != n)
	{
		merge(a, c, k * (j + 1), n - 1);
	}
	k++;
     }
}



int main(void)
{
    int n, key;
    double *a, t, *c;
    int res;
    const char* name = "A.txt";
    printf("Input n and key\n");
    if(scanf("%d%d", &n, &key)!= 2)
    {
        printf("Cannot read");
        return 1;
    }
    if(!(a = (double*)malloc(n*sizeof(double))))
    {
        printf("Not enough memory!\n");
        return 2;
    }
    if (key == 0)
    {
        res = read_array(name, a, n);
        if (res < 0)
	{
		switch (res)
		{
			case (-1):
			{
				printf("Cannot open %s\n", name);
				break;
			}
			case (-2):
			{
				printf("Cannot read %s\n", name);
				break;
			}
			default:
			{
				printf("Unknown error %d in %s\n", res,name);
			}
		}
			free(a); return 3;
		}


		if (res == 0)
        {
             printf("The file %s is empty\n", name);
             return 0;
        }
        else n = res;}
    else init_array(a, n, key);
    c = (double*)malloc(n*sizeof(double));
    sort(a, c, n);
    print_array(a, n);
    free(a);
    free(c);
    return 0;
}