Update most_char_num.md

修改一些小问题.

Author: pimgeek

most_char_num.md

@@ -65,20 +65,20 @@
 
 ; 定义函数 get-key-by-value
 ; 输入一个 Hash 表和一个 a-value (用于反向查找 key 的 value)
-; 输出相 value 等于 a-value 的那些 key,
+; 输出 value 等于 a-value 的那些 key,
 ; 换言之, 此 key 满足条件 (hash-ref key) == a-value.
 (define (get-key-by-value a-hash a-value)
   (hash-for-each a-hash
-                 (lambda (k v)
-                   (if (= a-value (hash-ref a-hash k))
-                       (printf "~a: ~a~n" k v) '()))))
+    (lambda (k v)
+      (if (= a-value (hash-ref a-hash k))
+        (printf "~a: ~a~n" k v) '()))))
 
 ; 定义函数 char-cmp
 ; 输入一个 preset-char (预设字符)
 ; 返回一个的匿名函数 (其内部包含 preset-char)
 ; > 其输入为 char-to-be-compared (待比较的字符)
-; > 当其 char-to-be-compared 与 preset-char 
-; > 一致时输出 true, 否则输出 false
+; > 当 char-to-be-compared 与 preset-char 
+; > 相等时输出 true, 否则输出 false
 (define (char-cmp preset-char)
   (lambda (char-to-be-compared)
     (if (char=? preset-char char-to-be-compared) true false)))
@@ -88,18 +88,20 @@
 ; 输出 a-string 中出现次数最多的字符, 及其出现次数
 (define (most-character-number a-string)
   (let*
-      ([all-chars-list (string->list a-string)]
-       [key-chars-list (delete-duplicates all-chars-list)]
-       [result-hash (make-hash)])
-    (begin
-      (for ([key-char key-chars-list])
-        (hash-set! result-hash
-                   key-char (count (char-cmp key-char) all-chars-list)))
+    ([all-chars-list (string->list a-string)]
+     [key-chars-list (delete-duplicates all-chars-list)]
+     [result-hash (make-hash)])
+    (for ([key-char key-chars-list])
+      (hash-set! result-hash
+        key-char (count (char-cmp key-char) all-chars-list)))
       (get-key-by-value 
-       result-hash 
-       (apply max (hash-values result-hash))))))
+        result-hash 
+        (apply max (hash-values result-hash)))))
 
-; 以下函数调用在正常运行之后, 应该显示 f:3 d:3 a: 3
+; 以下函数调用在正常运行之后, 应该显示
+; f: 3
+; d: 3
+; a: 3
 (most-character-number "ssfdaa dffda ")
 ```