diff --git a/README.md b/README.md
index 3f72893..d54f33e 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,5 @@
+[![Review Assignment Due Date](https://classroom.github.com/assets/deadline-readme-button-22041afd0340ce965d47ae6ef1cefeee28c7c493a6346c4f15d667ab976d596c.svg)](https://classroom.github.com/a/4nHL7_6-)
+[![Open in Visual Studio Code](https://classroom.github.com/assets/open-in-vscode-2e0aaae1b6195c2367325f4f02e2d04e9abb55f0b24a779b69b11b9e10269abc.svg)](https://classroom.github.com/online_ide?assignment_repo_id=19096205&assignment_repo_type=AssignmentRepo)
 # CS 164: Programming Assignment 1
 
 [PA1 Specification]: https://drive.google.com/open?id=1oYcJ5iv7Wt8oZNS1bEfswAklbMxDtwqB
diff --git a/src/main/cup/chocopy/pa1/ChocoPy.cup b/src/main/cup/chocopy/pa1/ChocoPy.cup
index d4ff444..a5fac8d 100644
--- a/src/main/cup/chocopy/pa1/ChocoPy.cup
+++ b/src/main/cup/chocopy/pa1/ChocoPy.cup
@@ -144,6 +144,9 @@ action code {:
  */
 terminal NEWLINE;
 terminal String PLUS; 
+terminal String MINUS; 
+terminal String TIMES; 
+terminal String DIV; 
 terminal Integer NUMBER; 
 /* Returned by the lexer for erroneous tokens.  Since it does not appear in
  * the grammar, it indicates a syntax error. */
diff --git a/src/main/jflex/chocopy/pa1/ChocoPy.jflex b/src/main/jflex/chocopy/pa1/ChocoPy.jflex
index 9aafe7f..73633e6 100644
--- a/src/main/jflex/chocopy/pa1/ChocoPy.jflex
+++ b/src/main/jflex/chocopy/pa1/ChocoPy.jflex
@@ -71,6 +71,10 @@ IntegerLiteral = 0 | [1-9][0-9]*
 
   /* Operators. */
   "+"                         { return symbol(ChocoPyTokens.PLUS, yytext()); }
+  "-"                         { return symbol(ChocoPyTokens.MINUS, yytext()); }
+  "*"                         { return symbol(ChocoPyTokens.TIMES, yytext()); }
+  "/"                         { return symbol(ChocoPyTokens.DIV, yytext()); }
+
 
   /* Whitespace. */
   {WhiteSpace}                { /* ignore */ }