1 files changed, 72 insertions, 0 deletions
diff --git a/rushs/tinyprintf/levenshtein/levenshtein.c b/rushs/tinyprintf/levenshtein/levenshtein.c
new file mode 100644
index 0000000..4da9397
--- /dev/null
+++ b/rushs/tinyprintf/levenshtein/levenshtein.c
@@ -0,0 +1,72 @@
+#include "levenshtein.h"
+
+#include <stdio.h>
+
+size_t max(size_t a, size_t b)
+{
+    if (a >= b)
+    {
+        return a;
+    }
+    return b;
+}
+
+size_t min(size_t a, size_t b)
+{
+    if (a <= b)
+    {
+        return a;
+    }
+    return b;
+}
+
+size_t min_3(size_t a, size_t b, size_t c)
+{
+    if (a <= b)
+    {
+        if (a <= c)
+        {
+            return a;
+        }
+        return c;
+    }
+    else
+    {
+        if (b <= c)
+        {
+            return b;
+        }
+        return c;
+    }
+}
+
+size_t my_strlen(const char *s)
+{
+    size_t i;
+    for (i = 0; s[i]; i++)
+    {
+        continue;
+    }
+    return i;
+}
+
+size_t levenshtein(const char *s1, const char *s2)
+{
+    size_t l1 = my_strlen(s1);
+    size_t l2 = my_strlen(s2);
+    if (min(l1, l2) == 0)
+    {
+        return max(l1, l2);
+    }
+
+    if (s1[0] == s2[0])
+    {
+        return levenshtein(s1 + 1, s2 + 1);
+    }
+
+    size_t lev1 = levenshtein(s1 + 1, s2);
+    size_t lev2 = levenshtein(s1, s2 + 1);
+    size_t lev3 = levenshtein(s1 + 1, s2 + 1);
+
+    return 1 + min_3(lev1, lev2, lev3);
+}