Swap, anagrams, occurences

Fixed sorting title for strings.

snippets/anagrams-of-string-(with-duplicates).md

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+### Anagrams of string (with duplicates)
+
+Use recursion.
+For each letter in the given string, create all the partial anagrams for the rest of its letters.
+Use `map()` to combine the letter with each partial anagram, then `reduce()` to combine all anagrams in one array.
+Base cases are for string `length` equal to `2` or `1`.
+
+```js
+var anagrams = s => {
+  if(s.length <= 2)  return s.length === 2 ? [s, s[1] + s[0]] : [s];
+  return s.split('').reduce( (a,l,i) => {
+    anagrams(s.slice(0,i) + s.slice(i+1)).map( v => a.push(l+v) );
+    return a;
+  }, []);
+}
+```