各位大哥！这是朋友给的一个程序，刚学！不懂！哪个有空帮忙讲解下！尽量详细！谢谢！

real m1,m2,r,count,G=1.0

int li_i

sle_count.text = ""

m1 = double(em_m1.text)

m2 = double(em_m2.text)

r = double(em_r.text)

if em_m1.text="" then

messagebox('提示','请输入物体1的质量')

em_m1.setfocus()

return

end if

if em_m2.text="" then

messagebox('提示','请输入物体2的质量')

em_m2.setfocus()

return

end if

if em_r.text="" then

messagebox('提示','请输入中心距离')

em_r.setfocus()

return

end if

if r<=0 then

messagebox('提示','中心距离应大于0')

em_r.setfocus()

return

end if

for li_i =1 to 11

G = 0.1*G

next

G = 6.67*G

count =(m1*m2*g)/(r*r)

sle_count.text = String(count)