/* convert tabs in standard input to spaces in */
/* standard output while maintaining columns */

#include        <stdio.h>
#define         TABSIZE         8

/* prototype for function findstop */
int findstop(int *);

int main()
{
int c;          /* character read from stdin */
int posn = 0;   /* column position of character */
int inc;        /* column increment to tab stop */

while ((c = getchar()) != EOF)
	switch(c)
		{
		case '\t':              /* c is a tab */
			inc = findstop(&posn);
			for( ; inc > 0; inc-- )
				putchar(' ');
			break;
		case '\n':              /* c is a newline */
			putchar(c);
			posn = 0;
			break;
		default:                /* c is anything else */
			putchar(c);
			posn++;
			break;
		}
return 0;
}

/* compute size of increment to next tab stop */

int findstop(int *col)
{
int retval;
retval = (TABSIZE - (*col % TABSIZE));

/* increment argument (current column position) to next tabstop */
*col += retval;

return retval;          /* main gets how many blanks for filling */
}