diff --git a/data_structures/list_array.cpp b/data_structures/list_array.cpp
index c796ffef9..24b04867b 100644
--- a/data_structures/list_array.cpp
+++ b/data_structures/list_array.cpp
@@ -1,5 +1,9 @@
+/**
+ * @file list_array.cpp
+ * @todo Add documentation
+ * @warning The sorting algorithm is erroneous
+ */
 #include <iostream>
-using namespace std;
 
 struct list {
     int data[50];
@@ -17,6 +21,9 @@ struct list {
             return (BinarySearch(array, first, mid - 1, x));
         else if (x > array[mid])
             return (BinarySearch(array, mid + 1, last, x));
+
+        std::cerr << __func__ << ":" << __LINE__ << ": Undefined condition\n";
+        return -1;
     }
 
     int LinarSearch(int *array, int x) {
@@ -34,16 +41,14 @@ struct list {
 
         if (isSorted) {
             pos = BinarySearch(data, 0, top - 1, x);
-        }
-
-        else {
+        } else {
             pos = LinarSearch(data, x);
         }
 
         if (pos != -1) {
-            cout << "\nElement found at position : " << pos;
+            std::cout << "\nElement found at position : " << pos;
         } else {
-            cout << "\nElement not found";
+            std::cout << "\nElement not found";
         }
         return pos;
     }
@@ -69,14 +74,12 @@ struct list {
     void insert(int x) {
         if (!isSorted) {
             if (top == 49) {
-                cout << "\nOverflow";
+                std::cout << "\nOverflow";
             } else {
                 data[top] = x;
                 top++;
             }
-        }
-
-        else {
+        } else {
             int pos = 0;
 
             for (int i = 0; i < top - 1; i++) {
@@ -99,7 +102,7 @@ struct list {
 
     void Remove(int x) {
         int pos = Search(x);
-        cout << "\n" << data[pos] << " deleted";
+        std::cout << "\n" << data[pos] << " deleted";
         for (int i = pos; i < top; i++) {
             data[i] = data[i + 1];
         }
@@ -108,7 +111,7 @@ struct list {
 
     void Show() {
         for (int i = 0; i < top; i++) {
-            cout << data[i] << "\t";
+            std::cout << data[i] << "\t";
         }
     }
 };
@@ -118,27 +121,27 @@ int main() {
     int choice;
     int x;
     do {
-        cout << "\n1.Insert";
-        cout << "\n2.Delete";
-        cout << "\n3.Search";
-        cout << "\n4.Sort";
-        cout << "\n5.Print";
-        cout << "\n\nEnter Your Choice : ";
-        cin >> choice;
+        std::cout << "\n1.Insert";
+        std::cout << "\n2.Delete";
+        std::cout << "\n3.Search";
+        std::cout << "\n4.Sort";
+        std::cout << "\n5.Print";
+        std::cout << "\n\nEnter Your Choice : ";
+        std::cin >> choice;
         switch (choice) {
         case 1:
-            cout << "\nEnter the element to be inserted : ";
-            cin >> x;
+            std::cout << "\nEnter the element to be inserted : ";
+            std::cin >> x;
             L.insert(x);
             break;
         case 2:
-            cout << "\nEnter the element to be removed : ";
-            cin >> x;
+            std::cout << "\nEnter the element to be removed : ";
+            std::cin >> x;
             L.Remove(x);
             break;
         case 3:
-            cout << "\nEnter the element to be searched : ";
-            cin >> x;
+            std::cout << "\nEnter the element to be searched : ";
+            std::cin >> x;
             L.Search(x);
             break;
         case 4:
diff --git a/data_structures/trie_tree.cpp b/data_structures/trie_tree.cpp
index 66b67fbc0..a613ebd8f 100644
--- a/data_structures/trie_tree.cpp
+++ b/data_structures/trie_tree.cpp
@@ -74,6 +74,10 @@ bool deleteString(trie* root, std::string str, int index) {
             return true;
         }
     }
+
+    /* should not return here */
+    std::cout << __func__ << ":" << __LINE__ << "Should not reach this line\n";
+    return false;
 }
 
 int main() {