From ad8a07cf736913d756d5100efb517e19d10efdde Mon Sep 17 00:00:00 2001
From: aspwil <aspwil@users.noreply.github.com>
Date: Sun, 4 Apr 2021 06:18:34 -0600
Subject: [PATCH] fixed error caused by negative number for St instruction

---
 src/ndballsim/Parser.java | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/ndballsim/Parser.java b/src/ndballsim/Parser.java
index 8372854..9667483 100644
--- a/src/ndballsim/Parser.java
+++ b/src/ndballsim/Parser.java
@@ -414,6 +414,9 @@ public static Instr[] parse(String file, boolean unlimit) {
                                 error(lineNum, "String instruction requires a ending \"]\"  ex. St[num]");
                             }
                             try {
+                                if( Integer.parseInt(line.substring(3, line.length() - 1)) < 0){
+                                    error(lineNum, "String instruction only accepts non-negative numbers");
+                                }
                                 list.add(new Instr(pos, "St", Integer.parseInt(line.substring(3, line.length() - 1))));
                             } catch (NumberFormatException e) {
                                 //was not a number