Merge pull request #2445 from msisaifu/fix-typo

fix typo

9-regular-expressions/14-regexp-lookahead-lookbehind/1-find-non-negative-integers/solution.md

@@ -1,7 +1,7 @@
 
 The regexp for an integer number is `pattern:\d+`.
 
-We can exclude negatives by prepending it with the negative lookahead: `pattern:(?<!-)\d+`.
+We can exclude negatives by prepending it with the negative lookbehind: `pattern:(?<!-)\d+`.
 
 Although, if we try it now, we may notice one more "extra" result:
 

9-regular-expressions/14-regexp-lookahead-lookbehind/article.md

@@ -1,6 +1,6 @@
 # Lookahead and lookbehind
 
-Sometimes we need to find only those matches for a pattern that are followed or preceeded by another pattern.
+Sometimes we need to find only those matches for a pattern that are followed or preceded by another pattern.
 
 There's a special syntax for that, called "lookahead" and "lookbehind", together referred to as "lookaround".