C={}
function f(x,y,z)k=x..","..y..","..z
C[k]=C[k]or(x>y and f(f(x-5,y,z),f(y-5,z,x),f(z-5,x,y))or z)
return C[k]
end
repeat
a,b,c=io.read("*n","*n","*n")
until not c or print(f(a,b,c))
Note that non-ascii characters in the above source code will be escaped (such as \x9f).