1 files changed, 39 insertions, 22 deletions

diff --git a/string.cpp b/string.cpp
index 42e97cc..e75b50e 100644
--- a/string.cpp
+++ b/string.cpp
@@ -9,23 +9,41 @@
 
 MyString::MyString(int len) : str_(new char[len + 1]), length_(len)
 {
+    this->count++;
 }
 
-MyString::MyString(const char *str) : length_(strlen(str))
+MyString::MyString(const char *str) : str_(new char[strlen(str)+1]), length_(strlen(str))
 {
-    str_ = new char[length_ + 1];
     strcpy(str_, str);
+    this->count++;
 }
 
 MyString::MyString(const MyString& str) : str_(new char[str.length_ + 1]),
                                           length_(str.length_)
 {
     strcpy(str_, str.str_);
+    this->count++;
+}
+
+MyString& MyString::operator=(const MyString& rhs)
+{
+    /* don't do anything if object assigns itself */
+    if (this == &rhs)
+        return *this;
+
+    length_ = rhs.length_;
+    delete[] str_;
+    str_ = new char[ length_ + 1];
+    strcpy(str_, rhs.str_);
+
+    /* assignment operator requires this */
+    return *this;
 }
 
 MyString::~MyString()
 {
     delete[] str_;
+    this->count--;
 }
 
 int MyString::indexOf(char ch, int pos) const
@@ -41,6 +59,9 @@ int MyString::indexOf(char ch, int pos) const
     return -1;
 }
 
+/* define this field only once, .h is not the best place */
+size_t MyString::count = 0;
+
 bool MyString::isSubstring(const MyString& str) const
 {
     if (length_ < str.length_)
@@ -65,6 +86,9 @@ bool MyString::isSubstring(const MyString& str) const
     return false;
 }
 
+/* might seem redundant since constructor can create an object from char array
+ * and call other isSubstring method that takes in MyString type
+ */
 bool MyString::isSubstring(const char *str) const
 {
     int i, j, k;
@@ -109,21 +133,6 @@ MyString& MyString::concat(const char *str)
     return *this;
 }
 
-MyString& MyString::operator=(const MyString& rhs)
-{
-    /* don't do anything if object assigns itself */
-    if (this == &rhs)
-        return *this;
-
-    length_ = rhs.length_;
-    delete[] str_;
-    str_ = new char[ length_ + 1];
-    strcpy(str_, rhs.str_);
-
-    /* assignment operator requires this */
-    return *this;
-}
-
 bool operator==(const MyString& lhs, const MyString& rhs)
 {
     if (lhs.length_ != rhs.length_)
@@ -135,13 +144,17 @@ bool operator==(const MyString& lhs, const MyString& rhs)
         return false;
 }
 
-/* seems like the ostream& in front has nothing to do with dereferencing a pointer,
- * but it seems like the & is placed there so we can make consecutive overloaded
- * calls to cout, effectively chaining all of the calls
- */
+bool operator!=(const MyString& lhs, const MyString& rhs)
+{
+    return !(lhs == rhs);
+}
 
 /* right now I think the reference is used to avoid returning copy of ostream
- * so when calls are chained up we work on one ostream object only */
+ * so when calls are chained up we work on one ostream object only
+ *
+ * this function is in global scope, it is friend'ed to allow us access to data
+ * members of calss MyString
+ */
 std::ostream& operator<<(std::ostream& ostr, const MyString& rhs)
 {
     return (ostr << rhs.str_);
@@ -179,3 +192,7 @@ MyString::operator char*()
         return NULL;
 }
 
+MyString::operator const char*() const
+{
+    return this->str_;
+}