diff --git a/calc.py b/calc.py
index de80b21..f8516e2 100755
--- a/calc.py
+++ b/calc.py
@@ -49,33 +49,33 @@ def div(a, b):
 b = None
 op = None
 
-while (True):
+while True:
     # get input values
-    a = raw_input("Enter the first argument: ")
-    op = raw_input("Enter the operation: ")
-    b = raw_input("Enter the second argument: ")
+    a = input("Enter the first argument: ")
+    op = input("Enter the operation: ")
+    b = input("Enter the second argument: ")
     try:
         a = int(a)
         b = int(b)
     except ValueError:
-        print "Invalid number argument..."
+        print("Invalid number argument...")
         op = None
 
     # decide function
     if (op != None):
         if (op == "+"):
-            print "Sum: ", add(a, b)
+            print("Sum: ", add(a, b))
         elif (op == "-"):
-            print "Difference: ", sub(a, b)
+            print("Difference: ", sub(a, b))
         elif (op == "*"):
-            print "Product: ", mult(a, b)
+            print("Product: ", mult(a, b))
         elif (op == "/"):
-            print "Quotient: ", div(a, b)
+            print("Quotient: ", div(a, b))
         else:
-            print "Invalid operation..."
+            print("Invalid operation...")
 
-    q = raw_input("Quit? [y/n] ")
-    if (q == "y" or q == "Y"):
+    q = input("Quit? [y/n] ")
+    if q == "y" or q == "Y":
         break
 
 # -------------------------------------------------------- #