diff --git a/src/operations/node.c b/src/operations/node.c
index 42e1f94..321f1a1 100644
--- a/src/operations/node.c
+++ b/src/operations/node.c
@@ -14,7 +14,7 @@ struct Node* make_node(int type, struct Value* value, std::string id) {
   int i;
 
   /* allocate space */
-  struct Node* node = (struct Node*) malloc(sizeof(struct Node));
+  struct Node* node = new Node();
 
   /* set properties */
   node->type = type;
diff --git a/src/operations/operators.c b/src/operations/operators.c
index 99d70db..ba6b496 100644
--- a/src/operations/operators.c
+++ b/src/operations/operators.c
@@ -21,7 +21,7 @@ struct Value* add(struct Value* x, struct Value* y) {
   } else if (x->type == DOUBLE && y->type == LONG) {
     ans = make_double(get_double(x) + get_long(y));
   } else if (x->type == STRING && y->type == STRING) {
-    ans = make_string(strcat(get_string(x), get_string(y)));  
+    ans = make_string(get_string(x) + get_string(y));  
   } else { // Both are DOUBLE
     ans = make_double(get_double(x) + get_double(y));
   }
@@ -109,7 +109,7 @@ struct Value* less(struct Value* x, struct Value* y) {
   } else if (x->type == DOUBLE && y->type == LONG) {
     ans = make_boolean(get_double(x) < get_long(y));
   } else if (x->type == STRING && y->type == STRING) {
-    ans = make_boolean(strcmp(get_string(x), get_string(y)) < 0);
+    ans = make_boolean(get_string(x).compare(get_string(y)) < 0);
   } else { // Both are DOUBLE
     ans = make_boolean(get_double(x) < get_double(y));
   }
@@ -134,7 +134,7 @@ struct Value* greater(struct Value* x, struct Value* y) {
   } else if (x->type == DOUBLE && y->type == LONG) {
     ans = make_boolean(get_double(x) > get_long(y));
   } else if (x->type == STRING && y->type == STRING) {
-    ans = make_boolean(strcmp(get_string(x), get_string(y)) > 0);
+    ans = make_boolean(get_string(x).compare(get_string(y)) > 0);
   } else { // Both are DOUBLE
     ans = make_boolean(get_double(x) > get_double(y));
   }
@@ -159,7 +159,7 @@ struct Value* less_equal(struct Value* x, struct Value* y) {
   } else if (x->type == DOUBLE && y->type == LONG) {
     ans = make_boolean(get_double(x) <= get_long(y));
   } else if (x->type == STRING && y->type == STRING) {
-    ans = make_boolean(strcmp(get_string(x), get_string(y)) <= 0);
+    ans = make_boolean(get_string(x).compare(get_string(y)) <= 0);
   } else { // Both are DOUBLE
     ans = make_boolean(get_double(x) <= get_double(y));
   }
@@ -184,7 +184,7 @@ struct Value* greater_equal(struct Value* x, struct Value* y) {
   } else if (x->type == DOUBLE && y->type == LONG) {
     ans = make_boolean(get_double(x) >= get_long(y));
   } else if (x->type == STRING && y->type == STRING) {
-    ans = make_boolean(strcmp(get_string(x), get_string(y)) >= 0);
+    ans = make_boolean(get_string(x).compare(get_string(y)) >= 0);
   } else { // Both are DOUBLE
     ans = make_boolean(get_double(x) >= get_double(y));
   }
@@ -212,7 +212,7 @@ struct Value* equals(struct Value* x, struct Value* y) {
   } else if (x->type == BOOLEAN && y->type == BOOLEAN) {
     ans = make_boolean(get_long(x) == get_long(y));
   } else if (x->type == STRING && y->type == STRING) {
-    ans = make_boolean(strcmp(get_string(x), get_string(y)) == 0);
+    ans = make_boolean(get_string(x).compare(get_string(y)) == 0);
   } else { // Type is a mix between boolean and another type
     fprintf(stderr, "Error, cannot compare a boolean with another type.\n");
   }
@@ -240,7 +240,7 @@ struct Value* not_equals(struct Value* x, struct Value* y) {
   } else if (x->type == BOOLEAN && y->type == BOOLEAN) {
     ans = make_boolean(get_long(x) != get_long(y));
   } else if (x->type == STRING && y->type == STRING) {
-    ans = make_boolean(strcmp(get_string(x), get_string(y)) != 0);
+    ans = make_boolean(get_string(x).compare(get_string(y)) != 0);
   } else { // Type is a mix between boolean and another type
     fprintf(stderr, "Error, cannot compare a boolean with another type.\n");
   }
diff --git a/src/variables/environment.c b/src/variables/environment.c
index f89c0b3..74f99c6 100644
--- a/src/variables/environment.c
+++ b/src/variables/environment.c
@@ -5,7 +5,7 @@
 #include "variable.h"
 
 struct Environment* create_environment(void) {
-  struct Environment* env = (struct Environment*) malloc(sizeof(struct Environment));
+  struct Environment* env = new Environment();
   env->num_vars = 0;
   for(int i = 0; i < MAX_VARIABLES; i++) {
     env->vars[i] = NULL;
diff --git a/src/variables/value.c b/src/variables/value.c
index ee4892b..b3f2b81 100644
--- a/src/variables/value.c
+++ b/src/variables/value.c
@@ -1,12 +1,13 @@
-#include <stdio.h>
 #include <stdlib.h>
 #include "value.h"
+#include <string>
+#include <iostream>
 #include "../parser/parser.tab.h"
 
 
-struct Value* make_value(TypeTag type, long num, double dec, struct Node* expr, char* str) {
+struct Value* make_value(TypeTag type, long num, double dec, struct Node* expr, std::string str) {
     /* allocate space */
-  struct Value* val = (struct Value*) malloc(sizeof(struct Value));
+  struct Value* val = new Value();
 
   /* set properties */
   val->type = type;
@@ -25,24 +26,24 @@ struct Value* make_value(TypeTag type, long num, double dec, struct Node* expr,
 }
 
 struct Value* make_long(long num) {
-  return make_value(LONG, num, 0, NULL, NULL);
+  return make_value(LONG, num, 0, NULL, "");
 }
 struct Value* make_double(double dec) {
-  return make_value(DOUBLE, 0, dec, NULL, NULL);
+  return make_value(DOUBLE, 0, dec, NULL, "");
 }
 struct Value* make_true() {
-  return make_value(BOOLEAN, 1, 0, NULL, NULL);
+  return make_value(BOOLEAN, 1, 0, NULL, "");
 }
 struct Value* make_false() {
-  return make_value(BOOLEAN, 0, 0, NULL, NULL);
+  return make_value(BOOLEAN, 0, 0, NULL, "");
 }
 struct Value* make_boolean(int x) {
   return (x)? make_true() : make_false();
 }
 struct Value* make_expression(struct Node* expr) {
-  return make_value(LAMBDA, 0, 0, expr, NULL);
+  return make_value(LAMBDA, 0, 0, expr, "");
 }
-struct Value* make_string(char* str) {
+struct Value* make_string(std::string str) {
   return make_value(STRING, 0, 0, NULL, str);
 }
 
@@ -59,7 +60,7 @@ double get_double(struct Value* val) {
 struct Node* get_expression(struct Value* val) {
   return val->value.expr;
 }
-char* get_string(struct Value* val) {
+std::string get_string(struct Value* val) {
   return val->value.str;
 }
 
@@ -75,7 +76,7 @@ void set_expression(struct Value* val, struct Node* expr) {
   val->type = LAMBDA;
   val->value.expr = expr;
 }
-void set_sring(struct Value* val, char* str) {
+void set_sring(struct Value* val, std::string str) {
   val->type = STRING;
   val->value.str = str;
 }
@@ -83,17 +84,17 @@ void set_sring(struct Value* val, char* str) {
 void print_value(struct Value* val) {
   if (val->type == BOOLEAN) {
     if (get_long(val)) {
-      printf("true");
+      std::cout << "true";
     } else {
-      printf("false");
+      std::cout << "false";
     }
   } else if (val->type == LONG) {
-    printf("%li", get_long(val));
+    std::cout << get_long(val);
   } else if (val->type == STRING) {
-    printf("%s", get_string(val));
+    std::cout << get_string(val);
   } else if (val->type == DOUBLE) {
-    printf("%lf", get_double(val));
+    std::cout << get_double(val);
   } else { // Assume lambda expression
-    printf("<LambdaExpression>");
+    std::cout << "<LambdaExpression>";
   }
 }
diff --git a/src/variables/value.h b/src/variables/value.h
index 4167813..00d281d 100644
--- a/src/variables/value.h
+++ b/src/variables/value.h
@@ -1,14 +1,20 @@
 #ifndef VALUE_H
 #define VALUE_H
 
+#include <string>
+
 enum TypeTag { DOUBLE, LONG, BOOLEAN, STRING, LAMBDA };
 
-typedef union typeval {
-        long num;
-        double dec;
-        struct Node* expr;
-        char* str;
-} TypeVal;
+union TypeVal {
+  long num;
+  double dec;
+  struct Node* expr;
+  std::string str;
+  TypeVal() {} 
+  // TypeVal(const std::string& s) : str(s) {} // Construct Point object using initializer list.
+  // TypeVal& operator=(const std::string& s) { new(&str) std::string(s); return *this; } // Assign Point object using placement 'new'.
+  ~TypeVal() {}
+};
 
 struct Value {
   enum TypeTag type;
@@ -16,14 +22,14 @@ struct Value {
 };
 
 // Constructors
-struct Value* make_value(int type, long num, double dec, struct Node* expr, char* str);
+struct Value* make_value(int type, long num, double dec, struct Node* expr, std::string str);
 struct Value* make_long(long num);
 struct Value* make_double(double dec);
 struct Value* make_true();
 struct Value* make_false();
 struct Value* make_boolean(int x);
 struct Value* make_expression(struct Node* expr);
-struct Value* make_string(char* str);
+struct Value* make_string(std::string str);
 
 // Destructor
 void delete_value(struct Value* val);
@@ -32,13 +38,13 @@ void delete_value(struct Value* val);
 long get_long(struct Value* val);
 double get_double(struct Value* val);
 struct Node* get_expression(struct Value* val);
-char* get_string(struct Value* val);
+std::string get_string(struct Value* val);
 
 // Setters
 void set_long(struct Value* val, long num);
 void set_double(struct Value* val, double dec);
 void set_expression(struct Value* val, struct Node* node);
-void set_string(struct Value* val, char* str);
+void set_string(struct Value* val, std::string str);
 
 void print_value(struct Value* val);
 
diff --git a/src/variables/variable.c b/src/variables/variable.c
index 60a3951..9b6c942 100644
--- a/src/variables/variable.c
+++ b/src/variables/variable.c
@@ -6,7 +6,7 @@
 /* creates a new variable and returns it */
 struct Variable* make_variable(char* id, struct Value* value) {
   /* allocate space */
-  struct Variable* var = (struct Variable*) malloc(sizeof(struct Variable));
+  struct Variable* var = new Variable();
 
   /* set properties */
   strcpy(var->id, id);