C	PROGRAM DRAND
C	AREA BY MONTE CARLO
1000	FORMAT(/' GIVE XLOW,XHIGH, YLOW,YHIGH,STARTING #, # SAMPLES'/5X,$)
1010	FORMAT(4F,2I)
1040	FORMAT(/' SAMPLE',I3,F10.6,5H AREA,
	1F10.0,6H UNDER,F10.0,5H OVER/
	2F23.9,' X'/F23.9, ' Y')
1	TYPE 1000
	ACCEPT 1010,XL,XH,YL,YH,K,NSAMP
	XFACT=XH-XL
	YFACT=YH-YL
	IF(XFACT*YFACT) 2,2,3
2	CALL EXIT
3	OVER=0.
	UNDER=0.
	DO 40 N=1,NSAMP
	DO 30 I=1,100
	X=XFACT*RAND(K)
	Y=YFACT*RAND(K)
	YC=TEST(X)
	IF(YC-Y)10,10,20
10	OVER=OVER+1
	GO TO 30
20	UNDER=UNDER+1
30	CONTINUE
	AREA=(XFACT*YFACT)*(UNDER/(UNDER+OVER))
40	TYPE 1040,N,AREA,UNDER,OVER,X,Y
	GO TO 1
	END
	FUNCTION TEST(XX)
	TEST=SIN(XX)
	RETURN
	END

