Are there any algorithms for scrambling a word? [closed]

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I am trying to make a word scrambler and am wondering if there are any algorithms I should use or if I should just build it from scratch. Any pointers would be helpful!

Answer 1

The standard algorithm for finding a random permutation of a sequence of elements (or, in your case, letters in a word) is the Fisher-Yates shuffle, which in linear time produces a truly random permutation of a sequence of elements. The algorithm is well-established and many standard libraries provide implementations of it (for example, the C++ std::random_shuffle algorithm is typically implemented using this algorithm), so you may be able to find a prewritten implementation. If not, the algorithm is extremely easy to implement, and here's some pseudocode for it:

for each index i = 0 to n - 1, inclusive:
    choose a random index j in the range i to n - 1, inclusive.
    swap A[i] and A[j]

Be careful when implementing this that when picking a random index, you do not pick an index between 0 and n-1 inclusive; this produces a nonuniform distribution of letters (you can read more about that in this earlier question).

Hope this helps!

Answer 2

Go with the Knuth Shuffle (AKA the Fisher–Yates Shuffle). It has the desirable feature of ensuring that every permutation of the set is equally likely. Here's a link to an implementation in C (along with implementations in other languages) that works on arbitrarily sized objects.