Files
c3c/resources/examples/levenshtein.c3

26 lines
815 B
C

module levenshtein;
import std::math;
// This levenshtein exercises C3 subarrays.
fn int levenshtein(char[] s, char[] t)
{
// if either string is empty, difference is inserting all chars
// from the other
if (!s.len) return t.len;
if (!t.len) return s.len;
// if last letters are the same, the difference is whatever is
// required to edit the rest of the strings
if (s[^1] == t[^1]) return levenshtein(s[0..^2], t[0..^2]);
// else try:
// changing last letter of s to that of t; or
// remove last letter of s; or
// remove last letter of t,
// any of which is 1 edit plus editing the rest of the strings
int a = levenshtein(s[0..^2], t[0..^2]);
int b = levenshtein(s, t[0..^2]);
int c = levenshtein(s[0..^2], t);
return @min(@min(a, b), c) + 1;
}