Hitler's Suicide

One jewish man tells a joke to a woman, so he says:

"Why did hitler commit suicide?"

She said: "I don't know."

he replies:"....He saw the gas bill."

Then she said:"That's horrible! How could you say that!"

And he replies: "I'm sorry, I really shouldn't be joking about the holocaust. My great grandfather died in concentration camp."

The girl replies: "I'm so sorry to hear that."

And he says: "Yeah, it's sad, he fell off the guard tower."