diff --git a/src/lexer.l b/src/lexer.l
index 9c0d989..6c6c927 100644
--- a/src/lexer.l
+++ b/src/lexer.l
@@ -39,8 +39,9 @@ DIGIT [0-9]
 "while"                 {return WHILE;}
 "print"                 {return PRINT;}
 "input"                 {return INPUT;}
-{DIGIT}*"."?{DIGIT}+    {yylval.value = make_node(VALUE, atof(yytext), ""); return VALUE;}
-[_a-zA-Z][_a-zA-Z0-9]*  {yylval.value = make_node(IDENTIFIER,  0, strdup(yytext)); return IDENTIFIER;}
+{DIGIT}                 {yylval.value = make_node(VALUE, make_value(LONG, atoi(yytext), 0), ""); return VALUE;}
+{DIGIT}*"."?{DIGIT}+    {yylval.value = make_node(VALUE, make_value(DOUBLE, 0, atof(yytext)), ""); return VALUE;}
+[_a-zA-Z][_a-zA-Z0-9]*  {yylval.value = make_node(IDENTIFIER,  NULL, strdup(yytext)); return IDENTIFIER;}
 [\n]                    {linenum++;} 
 [ \t\r]+                {}
 .                       {printf("Error: invlaid lexeme '%s'.\n", yytext); return 0;}
diff --git a/src/node.h b/src/node.h
index e607b1c..3b410cb 100644
--- a/src/node.h
+++ b/src/node.h
@@ -6,13 +6,16 @@
 #define STATEMENT 200
 #define MAX_VARIABLES 200
 
+#define DOUBLE 300
+#define LONG 301
+
 // Share the line number between files
 extern int linenum;
 
 /* a tree node definition */
 struct Node {
   int type;
-  double value;
+  struct Value* value;
 
   /* the id of the node (used for identifiers only) */
   char id[ID_SIZE];
@@ -23,7 +26,7 @@ struct Node {
 };
 
 // Abstract Syntax Tree Functions
-struct Node* make_node(int type, double value, char* id);
+struct Node* make_node(int type, struct Value* value, char* id);
 void attach_node(struct Node* parent, struct Node* child);
 void print_tree(struct Node* node, int tabs);
 void delete_tree(struct Node* node);
@@ -31,7 +34,7 @@ void delete_tree(struct Node* node);
 
 struct Variable {
   char id[ID_SIZE];
-  double value;
+  struct Value* value;
 };
 
 typedef union typeval {
@@ -45,15 +48,17 @@ struct Value {
 };
 
 // Value functions
-int get_int(struct Value* val);
+struct Value* make_value(int type, long num, double dec);
+void delete_value(struct Value* val);
+long get_long(struct Value* val);
 double get_double(struct Value* val);
-void set_int(struct Value* val);
-void set_double(struct Value* val);
+void set_long(struct Value* val, long num);
+void set_double(struct Value* val, double dec);
 
 // Variable Functions
-struct Variable* make_variable(char* id, double value);
-void set_value(struct Variable* var, double value);
-double get_value(struct Variable* var);
+struct Variable* make_variable(char* id, struct Value* value);
+void set_value(struct Variable* var, struct Value* value);
+struct Value* get_value(struct Variable* var);
 
 struct Environment {
   int num_vars;
@@ -69,6 +74,6 @@ void add_variable(struct Environment* env, struct Variable* var);
 
 // Interpreting AST
 void eval_statement(struct Node* node, struct Environment* env);
-double eval_expression(struct Node* node, struct Environment* env);
+struct Value* eval_expression(struct Node* node, struct Environment* env);
 
 #endif
diff --git a/src/parser.y b/src/parser.y
index e5c8565..c9e9db9 100644
--- a/src/parser.y
+++ b/src/parser.y
@@ -70,32 +70,32 @@ statement: assignment { $$ = $1; }
          | statements { $$ = $1; } 
 
 assignment: ident ASSIGN expression SEMICOLON {
-    $$ = make_node(ASSIGN, 0, "");
+    $$ = make_node(ASSIGN, NULL, "");
     attach_node($$, $1);
     attach_node($$, $3);
 }
 
 if-statement: IF expression THEN statement {
-    $$ = make_node(IF, 0, "");
+    $$ = make_node(IF, NULL, "");
     attach_node($$, $2);
     attach_node($$, $4);
 }
 
 if-else-statement: IF expression THEN statement ELSE statement {
-    $$ = make_node(IF, 0, "");
+    $$ = make_node(IF, NULL, "");
     attach_node($$, $2);
     attach_node($$, $4);
     attach_node($$, $6);
 }
 
 while: WHILE expression DO statement {
-    $$ = make_node(WHILE, 0, "");
+    $$ = make_node(WHILE, NULL, "");
     attach_node($$, $2);
     attach_node($$, $4);
 }
 
 print: PRINT expression SEMICOLON {
-    $$ = make_node(PRINT, 0, "");
+    $$ = make_node(PRINT, NULL, "");
     attach_node($$, $2);
 }
 
@@ -103,31 +103,31 @@ print: PRINT expression SEMICOLON {
 statements: BEGINTOK substatements END { $$ = $2; }
           | BEGINTOK END {}
 
-substatements: statement substatements {$$ = make_node(STATEMENT, 0, ""); attach_node($$, $1); attach_node($$, $2); }
-              | statement  {$$ = make_node(STATEMENT, 0, ""); attach_node($$, $1); }
+substatements: statement substatements {$$ = make_node(STATEMENT, NULL, ""); attach_node($$, $1); attach_node($$, $2); }
+              | statement  {$$ = make_node(STATEMENT, NULL, ""); attach_node($$, $1); }
 
-expression : expression OR subexpression { $$ = make_node(OR, 0, ""); attach_node($$, $1); attach_node($$, $3);}
-     | expression AND subexpression { $$ = make_node(AND, 0, ""); attach_node($$, $1); attach_node($$, $3);}
+expression : expression OR subexpression { $$ = make_node(OR, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
+     | expression AND subexpression { $$ = make_node(AND, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
      | subexpression { $$ = $1; }
 
-subexpression: subexpression LESS term { $$ = make_node(LESS, 0, ""); attach_node($$, $1); attach_node($$, $3);}
-     | subexpression LESSEQ term { $$ = make_node(LESSEQ, 0, ""); attach_node($$, $1); attach_node($$, $3);}
-     | subexpression GREATER term { $$ = make_node(GREATER, 0, ""); attach_node($$, $1); attach_node($$, $3);}
-     | subexpression GREATEREQ term { $$ = make_node(GREATEREQ, 0, ""); attach_node($$, $1); attach_node($$, $3);}
-     | subexpression EQUALS term { $$ = make_node(EQUALS, 0, ""); attach_node($$, $1); attach_node($$, $3);}
-     | subexpression NEQUALS term { $$ = make_node(NEQUALS, 0, ""); attach_node($$, $1); attach_node($$, $3);}
+subexpression: subexpression LESS term { $$ = make_node(LESS, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
+     | subexpression LESSEQ term { $$ = make_node(LESSEQ, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
+     | subexpression GREATER term { $$ = make_node(GREATER, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
+     | subexpression GREATEREQ term { $$ = make_node(GREATEREQ, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
+     | subexpression EQUALS term { $$ = make_node(EQUALS, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
+     | subexpression NEQUALS term { $$ = make_node(NEQUALS, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
      | term { $$ = $1; }
 
-term : term PLUS subterm { $$ = make_node(PLUS, 0, ""); attach_node($$, $1); attach_node($$, $3);}
-     | term MINUS subterm { $$ = make_node(MINUS, 0, ""); attach_node($$, $1); attach_node($$, $3);}
+term : term PLUS subterm { $$ = make_node(PLUS, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
+     | term MINUS subterm { $$ = make_node(MINUS, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
      | subterm { $$ = $1; }
 
-subterm: subterm TIMES factor { $$ = make_node(TIMES, 0, ""); attach_node($$, $1); attach_node($$, $3);}
-       | subterm DIVIDE factor { $$ = make_node(DIVIDE, 0, ""); attach_node($$, $1); attach_node($$, $3);}
+subterm: subterm TIMES factor { $$ = make_node(TIMES, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
+       | subterm DIVIDE factor { $$ = make_node(DIVIDE, NULL, ""); attach_node($$, $1); attach_node($$, $3);}
        | factor { $$ = $1; }
 
-factor : MINUS factor { $$ = make_node(MINUS, 0, ""); attach_node($$, $2); }
-       | NOT factor { $$ = make_node(NOT, 0, ""); attach_node($$, $2); }
+factor : MINUS factor { $$ = make_node(MINUS, NULL, ""); attach_node($$, $2); }
+       | NOT factor { $$ = make_node(NOT, NULL, ""); attach_node($$, $2); }
        | atom { $$ = $1; }
 
 atom: OPENPAREM expression ENDPAREM { $$ = $2; }
@@ -137,7 +137,7 @@ ident: IDENTIFIER { $$ = $1; }
 
 identvalue: IDENTIFIER { $$ = $1; }
           | VALUE { $$ = $1; }
-          | INPUT { $$ = make_node(INPUT, 0 , ""); }
+          | INPUT { $$ = make_node(INPUT, NULL , ""); }
 
 
 
@@ -184,7 +184,7 @@ int main(int argc, char* argv[]) {
 
 
 /* creates a new node and returns it */
-struct Node* make_node(int type, double value, char* id) {
+struct Node* make_node(int type, struct Value* value, char* id) {
   int i;
 
   /* allocate space */
@@ -212,6 +212,7 @@ void attach_node(struct Node* parent, struct Node* child) {
 }
 
 void print_tree(struct Node* node, int tabs) {
+  int i;
   /* base case */
   if(!node) {
     fprintf(stderr, "NO TREE STRUCTURE\n");
@@ -219,13 +220,12 @@ void print_tree(struct Node* node, int tabs) {
   }
 
   /* print leading tabs */
-  for(int i = 0; i < tabs; i++) {
+  for(i = 0; i < tabs; i++) {
     printf("    ");
   }
 
   switch(node->type) {
     case IDENTIFIER: printf("IDENTIFIER: %s\n", node->id); break;
-    case VALUE: printf("VALUE: %lf\n", node->value); break;
     case PLUS: printf("PLUS:\n"); break;
     case MINUS: printf("MINUS:\n"); break;
     case DIVIDE: printf("DIVIDE:\n"); break;
@@ -245,6 +245,13 @@ void print_tree(struct Node* node, int tabs) {
     case PRINT: printf("PRINT:\n"); break;
     case INPUT: printf("INPUT:\n"); break;
     case STATEMENT: printf("STATEMENT:\n"); break;
+    case VALUE: 
+      if (node->value->type == LONG) {
+        printf("VALUE: %li\n", get_long(node->value));
+      } else { // Assume double
+        printf("VALUE: %lf\n", get_double(node->value));
+      }
+     break;
     default:
       printf("Error, %d not a valid node type.\n", node->type);
       exit(1);
@@ -265,7 +272,7 @@ void delete_tree(struct Node* node) {
 }
 
 /* creates a new variable and returns it */
-struct Variable* make_variable(char* id, double value) {
+struct Variable* make_variable(char* id, struct Value* value) {
   /* allocate space */
   struct Variable* var = malloc(sizeof(struct Variable));
 
@@ -277,12 +284,12 @@ struct Variable* make_variable(char* id, double value) {
   return var;
 }
 
-void set_value(struct Variable* var, double value) {
+void set_value(struct Variable* var, struct Value* value) {
   if (!var) { fprintf(stderr, "Error: Invalid Variable\n"); return; }
   var->value = value;
 }
 
-double get_value(struct Variable* var) {
+struct Value* get_value(struct Variable* var) {
   if (!var) { fprintf(stderr, "Error: Invalid Variable\n"); return 0; }
   return var->value;
 }
@@ -337,7 +344,281 @@ void check_num_nodes(struct Node* node, int num_children, char* error) {
   }
 }
 
-double eval_expression(struct Node* node, struct Environment* env) {
+struct Value* make_value(int type, long num, double dec) {
+    /* allocate space */
+  struct Value* val = malloc(sizeof(struct Value));
+
+  /* set properties */
+  val->type = type;
+  if (type == LONG) {
+    val->value.num = num;
+  } else { // Assume DOUBLE
+    val->value.dec = dec;
+  }
+
+  /* return new variable */
+  return val;
+}
+void delete_value(struct Value* val) {
+  free(val);
+}
+long get_long(struct Value* val) {
+  return val->value.num;
+}
+double get_double(struct Value* val) {
+  return val->value.dec;
+}
+void set_long(struct Value* val, long num) {
+  val->type = LONG;
+  val->value.num = num;
+}
+void set_double(struct Value* val, double dec) {
+  val->type = DOUBLE;
+  val->value.dec = dec;
+}
+struct Value* add(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in add.\n"); }
+
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) + get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) + get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) + get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) + get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* subtract(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in subtract.\n"); }
+  
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) - get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) - get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) - get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) - get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* division(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in divide.\n"); }
+  
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) / get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) / get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) / get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) / get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* multiplication(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in multiply.\n"); }
+  
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) * get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) * get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) * get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) * get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* less(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in <.\n"); }
+
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) < get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) < get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) < get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) < get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* greater(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in greater.\n"); }
+
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) > get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) > get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) > get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) > get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* less_equal(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in <=.\n"); }
+
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) <= get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) <= get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) <= get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) <= get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* greater_equal(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in >=.\n"); }
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) >= get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) >= get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) >= get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) >= get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* equals(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in ==.\n"); }
+  
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) == get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) == get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) == get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) == get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* not_equals(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in !=.\n"); }
+  
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) != get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) != get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) != get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) != get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* and(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in &&.\n"); }
+
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) && get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) && get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) && get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) && get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* or(struct Value* x, struct Value* y) {
+  if (!x || !y) { fprintf(stderr, "Error, uninitialized values being used in ||.\n"); }
+
+  struct Value* ans;
+
+  // Destruct all four cases
+  if (x->type == LONG && y->type == LONG) {
+    ans = make_value(LONG, get_long(x) || get_long(y), 0);
+  } else if (x->type == LONG && y->type == DOUBLE) {
+    ans = make_value(DOUBLE, 0, get_long(x) || get_double(y));
+  } else if (x->type == DOUBLE && y->type == LONG) {
+    ans = make_value(DOUBLE, 0, get_double(x) || get_long(y));
+  } else { // Both are DOUBLE
+    ans = make_value(DOUBLE, 0, get_double(x) || get_double(y));
+  }
+
+  return ans;
+}
+
+struct Value* not(struct Value* x) {
+  if (!x) { fprintf(stderr, "Error, uninitialized values being used in !.\n"); }
+
+  struct Value* ans;
+
+  // Destruct all two cases
+  if (x->type == LONG) {
+    ans = make_value(LONG, !get_long(x), 0);
+  } else { // Assume it's a double
+    ans = make_value(DOUBLE, 0, !get_double(x));
+  }
+
+  return ans;
+}
+
+struct Value* eval_expression(struct Node* node, struct Environment* env) {
   /* base case */
   if(!node) {
     fprintf(stderr, "Error: No tree structure to evaluate\n");
@@ -349,13 +630,16 @@ double eval_expression(struct Node* node, struct Environment* env) {
   struct Variable* var = NULL;
 
   // Evaluate subexpressions if existent
-  double val1, val2, val3;
+  struct Value* val1 = NULL;
+  struct Value* val2 = NULL;
+  struct Value* val3 = NULL;
   if (node->num_children > 0) {
     val1 = eval_expression(node->children[0], env);
     if (node->num_children > 1) {
       val2 = eval_expression(node->children[1], env);
       if (node->num_children > 2) {
         val3 = eval_expression(node->children[2], env);
+        // delete_value(val3); // No code below uses val3 for now...
       }
     }
   }
@@ -363,73 +647,87 @@ double eval_expression(struct Node* node, struct Environment* env) {
   switch(node->type) {
     case PLUS:
       check_num_nodes(node, 2, "cannot add more than two expressions.");
-      return val1 + val2;
+      return add(val1, val2);
+      // return val1 + val2;
       break;
     //----------
     case MINUS:
       check_num_nodes(node, 2, "cannot subtract more than two expressions.");
-      return val1 - val2;
+      return subtract(val1, val2);
+      // return val1 - val2;
       break;
     //----------
     case DIVIDE:
       check_num_nodes(node, 2, "cannot divide more than two expressions.");
-      return val1 / val2;
+      return division(val1, val2);
+      // return val1 / val2;
       break;
     //----------
     case TIMES:
       check_num_nodes(node, 2, "cannot multiply more than two expressions.");
-      return val1 * val2;
+      return multiplication(val1, val2);
+      // return val1 * val2;
       break;
     //----------
     case LESS:
       check_num_nodes(node, 2, "cannot compare more than two expressions.");
       if (node->num_children != 2) { fprintf(stderr, "Error, cannot compare more than two expressions.\n"); } 
-      return val1 < val2;
+      return less(val1, val2);
+      // return val1 < val2;
       break;
     //----------
     case GREATER:
       check_num_nodes(node, 2, "cannot compare more than two expressions.");
-      return val1 > val2;
+      return greater(val1, val2);
+      // return val1 > val2;
       break;
     //----------
     case LESSEQ:
       check_num_nodes(node, 2, "cannot compare more than two expressions.");
-      return val1 <= val2;
+      return less_equal(val1, val2);
+      // return val1 <= val2;
       break;
     //----------
     case GREATEREQ:
       check_num_nodes(node, 2, "cannot compare more than two expressions.");
-      return val1 >= val2;
+      return greater_equal(val1, val2);
+      // return val1 >= val2;
       break;
     //----------
     case EQUALS:
       check_num_nodes(node, 2, "cannot compare more than two expressions.");
-      return val1 == val2;
+      return equals(val1, val2);
+      // return val1 == val2;
       break;
     //----------
     case NEQUALS:
       check_num_nodes(node, 2, "cannot compare more than two expressions.");
-      return val1 != val2;
+      return not_equals(val1, val2);
+      // return val1 != val2;
       break;
     //----------
     case AND:
       check_num_nodes(node, 2, "cannot perform logical operators on more than two expressions.");
-      return val1 && val2;
+      return and(val1, val2);
+      // return val1 && val2;
       break;
     //----------
     case OR:
       check_num_nodes(node, 2, "cannot perform logical operators on more than two expressions.");
-      return val1 || val2;
+      return or(val1, val2);
+      // return val1 || val2;
       break;
     //----------
     case NOT:
       check_num_nodes(node, 1, "cannot negate more than one expressions.");
-      return !val1;
+      return not(val1);
+      // return !val1;
       break;
     //----------
-    case INPUT:
+    case INPUT: // We're only going to support reading in doubles
+      // Look into deleting possible values...?
       scanf("%lf", &temp);
-      return temp;
+      return make_value(DOUBLE, 0, temp);
       break;
     //----------
     case IDENTIFIER:
@@ -459,6 +757,7 @@ void eval_statement(struct Node* node, struct Environment* env) {
     fprintf(stderr, "Error: No tree structure to evaluate\n");
     return;
   }
+  struct Value* tempVal;
 
   switch(node->type) {
     case ASSIGN:
@@ -472,23 +771,47 @@ void eval_statement(struct Node* node, struct Environment* env) {
       if (node->num_children != 2 && node->num_children != 3) { 
         fprintf(stderr, "Error: The format of an if-statement is if expression statement with an optional else.\n"); 
       }
-      if (eval_expression(node->children[0], env)) {
-        eval_statement(node->children[1], env);
-      } else if (node->num_children == 3) {
+      tempVal = eval_expression(node->children[0], env);
+      if (tempVal->type == LONG) {
+        if (get_long(tempVal)) {
+          eval_statement(node->children[1], env);
+        } else if (node->num_children == 3) {
         eval_statement(node->children[2], env);
+        }
+      } else { // Assume DOUBLE
+        if (get_double(tempVal)) {
+          eval_statement(node->children[1], env);
+        } else if (node->num_children == 3) {
+        eval_statement(node->children[2], env);
+        }
       }
       break;
     //------------
     case WHILE:
       check_num_nodes(node, 2, "the format of a while statement is: while expression statement(s)");
-      while (eval_expression(node->children[0], env)) {
-        eval_statement(node->children[1], env);
+      tempVal = eval_expression(node->children[0], env);
+      if (tempVal->type == LONG) {
+        while (get_long(tempVal)) {
+          eval_statement(node->children[1], env);
+          tempVal = eval_expression(node->children[0], env);
+        }
+      } else { // Assume DOUBLE
+        while (get_double(tempVal)) {
+          eval_statement(node->children[1], env);
+          tempVal = eval_expression(node->children[0], env);
+        }
       }
+
       break;
     //------------
     case PRINT:
       check_num_nodes(node, 1, "can only print out one expression at a time.");
-      printf("%lf\n", eval_expression(node->children[0], env));
+      tempVal = eval_expression(node->children[0], env);
+      if (tempVal->type == LONG) {
+        printf("%li\n", get_long(tempVal));
+      } else {
+        printf("%lf\n", get_double(tempVal));
+      }
       break;
     //------------
     case STATEMENT: // Can have a maximum of two children statement nodes