What means 20|10 ???

Answer 1

20 - 10100, 10 - 1010, 20|10 = 30, 11110

Answer 2

https://www.tutorialspoint.com/JUMP_LINK__&&__python__&&__JUMP_LINK/bitwise_operators_example.htm

it's a bitwise OR operator

Answer 3

thanks, u really helped me)