diff --git a/ch14/ex14_18_StrBlob.cpp b/ch14/ex14_18_StrBlob.cpp
index 2ea24ede..4b298ca8 100644
--- a/ch14/ex14_18_StrBlob.cpp
+++ b/ch14/ex14_18_StrBlob.cpp
@@ -9,32 +9,32 @@
 
 bool operator==(const StrBlob &lhs, const StrBlob &rhs)
 {
-	return *lhs.data == *rhs.data;
+    return *lhs.data == *rhs.data;
 }
 
 bool operator!=(const StrBlob &lhs, const StrBlob &rhs)
 {
-	return !(lhs == rhs);
+    return !(lhs == rhs);
 }
 
 bool operator< (const StrBlob &lhs, const StrBlob &rhs)
 {
-	return std::lexicographical_compare(lhs.data->begin(), lhs.data->end(), rhs.data->begin(), rhs.data->end());
+    return std::lexicographical_compare(lhs.data->begin(), lhs.data->end(), rhs.data->begin(), rhs.data->end());
 }
 
 bool operator> (const StrBlob &lhs, const StrBlob &rhs)
 {
-	return rhs < lhs;
+    return rhs < lhs;
 }
 
 bool operator<=(const StrBlob &lhs, const StrBlob &rhs)
 {
-	return !(rhs < lhs);
+    return !(rhs < lhs);
 }
 
 bool operator>=(const StrBlob &lhs, const StrBlob &rhs)
 {
-	return !(lhs < rhs);
+    return !(lhs < rhs);
 }
 
 //================================================================
@@ -45,32 +45,32 @@ bool operator>=(const StrBlob &lhs, const StrBlob &rhs)
 
 bool operator==(const StrBlobPtr &lhs, const StrBlobPtr &rhs)
 {
-	return lhs.curr == rhs.curr;
+    return lhs.curr == rhs.curr;
 }
 
 bool operator!=(const StrBlobPtr &lhs, const StrBlobPtr &rhs)
 {
-	return !(lhs == rhs);
+    return !(lhs == rhs);
 }
 
 bool operator< (const StrBlobPtr &x, const StrBlobPtr &y)
 {
-	return x.curr < y.curr;
+    return x.curr < y.curr;
 }
 
-bool operator> (const StrBlobPtr &x, const StrBlobPtr &y)
+bool operator>(const StrBlobPtr &x, const StrBlobPtr &y)
 {
-	return x.curr > y.curr;
+    return x.curr > y.curr;
 }
 
 bool operator<=(const StrBlobPtr &x, const StrBlobPtr &y)
 {
-	return x.curr <= y.curr;
+    return x.curr <= y.curr;
 }
 
 bool operator>=(const StrBlobPtr &x, const StrBlobPtr &y)
 {
-	return x.curr >= y.curr;
+    return x.curr >= y.curr;
 }
 
 //================================================================
@@ -81,32 +81,32 @@ bool operator>=(const StrBlobPtr &x, const StrBlobPtr &y)
 
 bool operator==(const ConstStrBlobPtr &lhs, const ConstStrBlobPtr &rhs)
 {
-	return lhs.curr == rhs.curr;
+    return lhs.curr == rhs.curr;
 }
 
 bool operator!=(const ConstStrBlobPtr &lhs, const ConstStrBlobPtr &rhs)
 {
-	return !(lhs == rhs);
+    return !(lhs == rhs);
 }
 
 bool operator< (const ConstStrBlobPtr &lhs, const ConstStrBlobPtr &rhs)
 {
-	return lhs.curr < rhs.curr;
+    return lhs.curr < rhs.curr;
 }
 
-bool operator> (const ConstStrBlobPtr &lhs, const ConstStrBlobPtr &rhs)
+bool operator>(const ConstStrBlobPtr &lhs, const ConstStrBlobPtr &rhs)
 {
-	return lhs.curr > rhs.curr;
+    return lhs.curr > rhs.curr;
 }
 
 bool operator<=(const ConstStrBlobPtr &lhs, const ConstStrBlobPtr &rhs)
 {
-	return lhs.curr <= rhs.curr;
+    return lhs.curr <= rhs.curr;
 }
 
 bool operator>=(const ConstStrBlobPtr &lhs, const ConstStrBlobPtr &rhs)
 {
-	return lhs.curr >= rhs.curr;
+    return lhs.curr >= rhs.curr;
 }
 
 //==================================================================
@@ -117,18 +117,18 @@ bool operator>=(const ConstStrBlobPtr &lhs, const ConstStrBlobPtr &rhs)
 
 StrBlob& StrBlob::operator=(const StrBlob &lhs)
 {
-	data = make_shared<vector<string>>(*lhs.data);
-	return *this;
+    data = make_shared<vector<string>>(*lhs.data);
+    return *this;
 }
 
 StrBlob& StrBlob::operator=(StrBlob &&rhs) NOEXCEPT
 {
-	if (this != &rhs) {
-		data = std::move(rhs.data);
-		rhs.data = nullptr;
-	}
+    if (this != &rhs) {
+        data = std::move(rhs.data);
+        rhs.data = nullptr;
+    }
 
-	return *this;
+    return *this;
 }
 
 //==================================================================
@@ -139,12 +139,12 @@ StrBlob& StrBlob::operator=(StrBlob &&rhs) NOEXCEPT
 
 StrBlobPtr StrBlob::begin()
 {
-	return StrBlobPtr(*this);
+    return StrBlobPtr(*this);
 }
 
 StrBlobPtr StrBlob::end()
 {
-	return StrBlobPtr(*this, data->size());
+    return StrBlobPtr(*this, data->size());
 }
 
 ConstStrBlobPtr StrBlob::cbegin() const