/* sorts an array of integers using selection sort */

#include <stdio.h>
#include <stdlib.h>

typedef int *LIST_PTR;

void swap(int *a , int *b);
int find_min_pos(int list[], int size, int start_pos);
void sel_sort(int list[], int size);
void fget_list(LIST_PTR *list, int *count) ;

int main(void)
{
 int i,count;
 LIST_PTR list;

 fget_list(&list, &count);
 sel_sort(list,count);
 for(i = 0; i < count; i++)
    printf("%d ", list[i]);

 free(list);
 return 0;
}

 /* reads all the integers in the file integer.dat into a dynamic array */
void fget_list(LIST_PTR *list, int *count)
{  FILE *inp;
   int n;
   LIST_PTR p;
   int cnt=0,i;

   inp=fopen("a:\\integers.dat","r");
   while (!feof(inp))
   { fscanf(inp,"%d",&n);
     cnt++;
   }
   rewind(inp);
   p=(LIST_PTR)malloc(cnt*sizeof(int));
   for (i=0; i<cnt; i++)
      fscanf(inp,"%d",&p[i]); 
   *list=p;
   *count=cnt;       
   fclose(inp);      
}

void sel_sort(int list[], int size)
{  int min_pos, start_pos;

   for(start_pos=0;  start_pos<size-1; start_pos++)
   {  min_pos=find_min_pos(list,size, start_pos);
      swap(&list[start_pos], &list[min_pos]);
   }
}


int find_min_pos(int list[], int size, int start_pos)
{  int i, min_pos=start_pos;
   
   for (i=start_pos+1; i<size; i++)
      if (list[i] < list[min_pos])
          min_pos = i;
   
   return min_pos;
}

void swap(int *a , int *b) {
   int temp = *a;
   *a =  *b;
   *b =  temp;
}