三、读程序(本大题共3小题，每小题5分，共15分)
1.SET TALK OFF
CLEA
INPUT "X=" TO X
S=1
IF X>=0
DO CASE
CASE X<10
S=1
CASE X<30
S=2
OTHERWISE
S=3
ENDC
ELSE
S=4
END IF
? S
SET TALK ON
当X输入为30时，S的输出结果为( )
A.4 B.3
C.2 D.1
2.SET TALK OFF
CLEAR
INPUT "A=" TO A
INPUT "B=" TO B
INPUT "C=" TO C
IF B D=A A=B B=D ENDIF IF C D=A A=C C=D ENDIF IF C D=B B=C C=D ENDIF ?A,B,C SET TALK ON 当从键盘输入A、B、C三个数值，该程序运行后其功能是( ) A.将它们从小到大排列后输出 B.将它们从大到小排列后输出 C.求三个数的平均值 D.将三个数任意排列 3.SET TALK OFF STORE 0 TO X,Y DO WHILE X<=10 X=X+1 IF INT(X/2)<>X/2 LOOP ELSE Y=Y+1 ENDIF ENDDO ?"Y=",Y SET TALK ON 该程序运行后的结果是( ) A.Y= 5 B.Y= 4 C.Y= 0 D.Y= 6
