4403 – strfry() gives skewed distributions

strfry() tries to shuffle its string using random swaps, but it uses the wrong strategy, and thus not all permutations are equally likely. The code doing the shuffling itself looks like this: len = strlen (string); for (i = 0; i < len; ++i) { int32_t j; char c; __random_r (&rdata, &j); j %= len; c = string[i]; string[i] = string[j]; string[j] = c; } In other words, for the string 'abc' j will alwa

[starwing]

正論過ぎて吹いた

[ultraist]

"This function is a joke."