QB编程序的问题，高手来！！！！

1.求两数的最大公约数、最小公倍数
2.求一数是否为素数

急，高手快来，加分多多（QBASIC）

---

1.cls
input A,B
for I=A to A * B
if I mod A = 0 and I mod B = 0 then print "zui xiao gong bei shu:";I
exit for
next I
for I=A to 1 step -1
if A mod I = 0 and B mod I = 0 then print "zui da gong yue shu:";I
exit for
next I
end

2.
cls
input A
if A mod 2 = 0 then print"旁谈No":end
for I=3 to A/渗悔2 step 2
if A mod I = 0 then print"运喊碰No":end
next I
print "Yes"
end

第一题可以用碾转相除:
cls
input A,B
A1=A:B1=B
if A1<B1 then swap A1,B1
do
A1=A1 mod B1
if A1= 0 then F=1:N=B1
B1=B1 mod A1
if B1= 0 then F=1:N=A1
loop until F=1
print N;
end

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求两数最族罩坦衡小公兆信闹倍数

100 INPUT "A=",A
110 INPUT "B=",B
120 DIM MAX, MIN, K
130 IF A>=B THEN MAX=A ELSE MAX=B
140 IF A<=B THEN MIN=A ELSE MIN=B
150 K = MAX MOD MIN
160 IF K = 0 GOTO 200
170 MAX = MIN
180 MIN = K
190 GOTO 150
200 PRINT A*B/MIN

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