C++ stack 자료구조 구현

  
#include
#include
FILE *in, *out;
int p[1000],i=0;
void push()
{
	i++;
	if(p[i]==EOF)
	{
		printf("EMPTY !\n");
	}
	else
	{
		while((fscanf(in,"%d",&p[i]))!=EOF)
		{		
			printf("p[%d] = %d\n",i++,p[i]);		
		}	
		i--;
	}
}
void top()
{
	if(p[i] != NULL)
	{
		fprintf(out,"%d\n",p[i]);
		printf("top[%d] = %d\n",i--,p[i]);
	}
	else
	{
		printf("EMPTY!!!!!\n");
	}
}
void main()
{
	char option;
	in = fopen("input.txt","r");
	out = fopen("output.txt","a");
	printf("넣기) p, 꺼내기) g, 끝내기) q \n"); 
	option = getch();
	switch(option)
	{
		case 'p':
		case 'P':
			{
				push();
				main();
				break;
			}
		case 'g':
		case 'G':
			{
				top();
				main();
				break;
			}
		case 'q':
		case 'Q':
		{
			break;
		}
		default:
			main();
			break;
	}	
	fclose(in);
	fclose(out);
}