SUBROUTINE PUSH(IDATA,ICOUNT)
C
C	THIS SUBROUTINE PUSHES THE ARRAY IDATA(ICOUNT) ONTO THE STACK
C
	INTEGER IDATA(ICOUNT)
	COMMON /STACK/IS,IMAX,ISTACK(100)
	DO 10 I	= 1,ICOUNT
	IS	= IS + 1
	IF(IS .GE. IMAX) GO TO 1000			!IF IS IS TOO BIG GIVE OVERFLOW ERROR
	ISTACK(IS)	= IDATA(I)
10	CONTINUE
D	WRITE(6,9000) IS,(ISTACK(J),J=1,IS)
D9000	FORMAT(40X' PUSH '10I7,(/40X,10I7))
	RETURN
1000	STOP '*** STACK OVERFLOW ***'
	END
	SUBROUTINE POP(IDATA,ICOUNT)
C
C	THIS SUBROUTINE FILLS ARRAY IDATA(ICOUNT) FROM THE STACK
C	THE STACK DECREASES BY ICOUNT.
C
	INTEGER IDATA(ICOUNT)
	COMMON /STACK/IS,IMAX,ISTACK(100)
	DO 10 I	= ICOUNT,1,-1
	IDATA(I)	= ISTACK(IS)
	IS	= IS - 1
D	WRITE(6,9000) IDATA(I),IS,I,ICOUNT
D9000	FORMAT(40X' POP  '10I7)
	IF(IS .LE. 0) GO TO 1000			!IS<0 MEANS STACK UNDERFLOW
10	CONTINUE
	RETURN
1000	STOP '*** STACK UNDERFLOW ***'
	END