Keg, 6 bytes
21½Ë/ℤ This defines the function f as:
- Taking a single parameter, then
- Calculating the square root of 2 by raising it to the power of 0.5, then
- Dividing the parameter by root 2, then
- Casting the result to an integer (truncating / flooring the result) and returning it.
The footer is to define the test cases in a nice way.
Explained in a usual way
21½Ë/ℤ 2 # Push 2 to the stack 1½ # Push 1 and halve it to get 0.5 Ë # Push 2 ** 0.5 (x ** 1/2 = sqrt(x)) /ℤ # Divide and cast to integer (floor) 🍟🍅
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