Samurai? or Ninja?

THere is no paticular joke related to Japanese culture that can be understood by foreigners who don't know our language.So I by myself created one joke to avoid you having wrong impression that Japan doen't have a sense of humor.

Question:Suppose you're lost in a way then happened to meet one Samurai and one Ninja.Which can you rely on to ask your way back to the right track?

Answer:Ninja,because....Samurai tells "some lie".

I know that native speaker has clear sound difference between "Sam" and "some","rai" and "lie".So if this joke had opposite effect of damaging the Japanese sense of humor,please wait for another one I create.