SimplifyPath corrected

Author: Hearen

LuoSonglei/week-3/RegxMatching.c

@@ -6,6 +6,8 @@ Description :
 Source      : https://leetcode.com/problems/regular-expression-matching/
 *******************************************/
 #include<stdbool.h>
+
+//this is version is too slow repeating the calculation process too many times - try to use DP to replace it;
 bool match(char* s, char* p)
 {
     return (*p == *s || (*p == '.' && *s != '\0'));
@@ -22,10 +24,12 @@ bool isMatch(char* s, char* p)
     }
     else
     {
-        if(isMatch(s, p+2)) 
+        if(isMatch(s, p+2)) //repeat the previous character zero time;
             return true;
-        while(match(s, p))
+        while(match(s, p)) //repeat the previous at least one time unitl it fits;
             if(isMatch(++s, p+2))
                 return true;
     }
 }
+
+

LuoSonglei/week-3/SimplifyPath.c

@@ -39,7 +39,7 @@ char* simplifyPath(char* path)
             unitSize = cur - pre - 1;
             if(unitSize < 0)//pre and cur point to the same position;
                 continue;
-            strncpy(unit, path+pre+1, unitSize);
+            strncpy(unit, path+pre+1, unitSize);//cur - pre > 0 is ensured;
             unit[unitSize] = '\0';
             pre = cur;
             if(strcmp(unit, ".") == 0 || strcmp(unit, "") == 0) //stay the same;