When eating sunflower seeds in the shell, how many calories does ones seed have, and how many calories are expended in cracking the shell and getting the seed out?

When my sister was my friend, back in 1987, she helped me change my eating habits. I wanted to lose about 30 pounds and keep it off. She taught me to count calories, something I still do to this day without even thinking about it.

She said sunflower seeds in the shell are a good snack. I said, “But seeds are fattening!”
She that was true, but getting the seed out of the shell uses up about as many calories as you take in per seed.

So, how do we figure this out?