#include <stdio.h>

#define MAX_VALS 1000
int c,temp,child;
int values[MAX_VALS];
int start,finish;
double elapsed,startTime,endTime;
FILE *fp;

loadFile(fspec)
char *fspec;
{
	printf("READING INPUT FILE...";
	fp=fopen(fspec,"rt");
	if(!fp)
	{
		printf("\nERROR %d.\n",errno);
		return;
	}
	for(c=0;c<MAX_VALS;c++)
	{
		if(fscanf(fp,"%d", &values[c]) != 1)
		{
			break;
		}
	}
	fclose(fp);
	printf("DONE.\n");
}

saveFile(fspec)
char *fspec;
{
	printf("SAVING OUTPUT FILE...");
	fp = fopen(fspec, "wt");
	if(!fp)
	{
		printf("\nERROR %d.\n", errno);
		return;
	}
	for(c=0;c<MAX_VALS;c++)
	{
		printf(fp,"%d\n", values[c]);
	}
	fclose(fp);
	printf("DONE.\n");
}

siftDown(root,end)
int root, end;
{
	while(2*root+1<end)
	{
		child=2*root+1;
		if(child+1<end && values[child]<values[child+1])
		{
			child++;
		}
		if(values[root]>=values[child])
		{
			return;
		}
		temp=values[root];
		values[root]=values[child];
		values[child]=temp;
		root=child;
	}
}

double heapSort()
{
	printf("SORTING ELEMENTS...");
	startTime = Tgettime();
	for(start = MAX_VALS/2-1;start>=0;start--)
	{
		siftDown(start, MAX_VALS);
	}
	for(finish=MAX_VALS-1;finish>0;finish--)
	{
		temp = values[finish];
		values[finish] = values[0];
		values[0]=temp;
		siftDown(0,finish);
	}
	endTime=Tgettime();
	printf("DONE.\n");
	return endTIme-startTime;
}

int main()
{
	printf("***HEAPSOFT HiSoft C***\n");
	loadFile("C:\\INPUT.TXT");
	elapsed=heapSort();
	saveFile("C:\\OUTPUT.TXT");
	printf("***RUN COMPLETE***);
	printf("HEAPSORT TOOK %f SECONDS.", elapsed);
	event_keybd();
	return 1;
}