A common task in programming interviews (not from my experience of interviews though) is to take a string or an integer and list every possible permutation. Is there an example of how this is done and the logic behind solving such a problem? I’ve seen a few code snippets but they weren’t well commented/explained and … Read more
I’m trying to write a function that does the following: takes an array of integers as an argument (e.g. [1,2,3,4]) creates an array of all the possible permutations of [1,2,3,4], with each permutation having a length of 4 the function below (I found it online) does this by taking a string as an argument, and … Read more
I’ve been using Random (java.util.Random) to shuffle a deck of 52 cards. There are 52! (8.0658175e+67) possibilities. Yet, I’ve found out that the seed for java.util.Random is a long, which is much smaller at 2^64 (1.8446744e+19). From here, I’m suspicious whether java.util.Random is really that random; is it actually capable of generating all 52! possibilities? … Read more
I have the following DataFrame: Col1 Col2 Col3 Type 0 1 2 3 1 1 4 5 6 1 … 20 7 8 9 2 21 10 11 12 2 … 45 13 14 15 3 46 16 17 18 3 … The DataFrame is read from a CSV file. All rows which have Type … Read more
How do you generate all the permutations of a list in Python, independently of the type of elements in that list? For example: permutations([]) [] permutations([1]) [1] permutations([1, 2]) [1, 2] [2, 1] permutations([1, 2, 3]) [1, 2, 3] [1, 3, 2] [2, 1, 3] [2, 3, 1] [3, 1, 2] [3, 2, 1] 40 … Read more
