function calculaterabbit(A,B)
a=-0.5
b=2.0
c=0.5
d=-1.0
rabbit=c*A+d*B
return rabbit
end
print("please input the number of foot")
A=io.read("*n")
print("please input the number of head")
B=io.read("*n")
rabbit=calculaterabbit(A,B)
chicken=B-rabbit
if(chicken>=0.01 and rabbit>=0.01 and (rabbit%1)==0 and (chicken%1)==0)
then
print("the number of rabbit is ",rabbit," , and the number of chicken is ", chicken)
else
print("error")
end