I am unable to figure out the output of the following program
big_num_1 = 1000
big_num_2 = 1000
small_num_1 = 1
small_num_2 = 1
big_num_1 is big_num_2 # False
small_num_1 is small_num_2 # True
What is happening above? Why is one False and other True.
Source: https://luminousmen.com/post/python-interview-questions-senior
Because is compares the identity of two objects (that is, if they're exactly the same object.) You want to test for equality, and for that you must use the == operator:
big_num_1 == big_num_2
=> True
small_num_1 == small_num_2
=> True
In case you're wondering why this example worked:
small_num_1 is small_num_2
=> True
It's because Python caches small (between -5 and 256) int objects internally, so the objects used in the comparison were taken from the cache and were the same. big_num_1 and big_num_2 are greater than 256, so they're represented by two different objects, and the identity test fails.
