update the comments

Author: haoel

algorithms/cpp/distinctSubsequences/distinctSubsequences.cpp

@@ -2,21 +2,51 @@
 // Author : Hao Chen
 // Date   : 2014-07-06
 
-/********************************************************************************** 
-* 
-* Given a string S and a string T, count the number of distinct subsequences of T in S.
-* 
-* A subsequence of a string is a new string which is formed from the original string 
-* by deleting some (can be none) of the characters without disturbing the relative positions 
-* of the remaining characters. (ie, "ACE" is a subsequence of "ABCDE" while "AEC" is not).
-* 
-* Here is an example:
-* S = "rabbbit", T = "rabbit"
-* 
-* Return 3.
-* 
-*               
-**********************************************************************************/
+/***************************************************************************************************** 
+ *
+ * Given a string S and a string T, count the number of distinct subsequences of S which equals T.
+ * 
+ * A subsequence of a string is a new string which is formed from the original string by deleting some 
+ * (can be none) of the characters without disturbing the relative positions of the remaining 
+ * characters. (ie, "ACE" is a subsequence of "ABCDE" while "AEC" is not).
+ * 
+ * Example 1:
+ * 
+ * Input: S = "rabbbit", T = "rabbit"
+ * Output: 3
+ * Explanation:
+ * 
+ * As shown below, there are 3 ways you can generate "rabbit" from S.
+ * (The caret symbol ^ means the chosen letters)
+ * 
+ * rabbbit
+ * ^^^^ ^^
+ * rabbbit
+ * ^^ ^^^^
+ * rabbbit
+ * ^^^ ^^^
+ * 
+ * Example 2:
+ * 
+ * Input: S = "babgbag", T = "bag"
+ * Output: 5
+ * Explanation:
+ * 
+ * As shown below, there are 5 ways you can generate "bag" from S.
+ * (The caret symbol ^ means the chosen letters)
+ * 
+ * babgbag
+ * ^^ ^
+ * babgbag
+ * ^^    ^
+ * babgbag
+ * ^    ^^
+ * babgbag
+ *   ^  ^^
+ * babgbag
+ *     ^^^
+ * 
+ ******************************************************************************************************/
 #include <stdlib.h>
 #include <time.h>
 #include <string.h>