diff --git a/practice/sandbox/.idea/vcs.xml b/practice/sandbox/.idea/vcs.xml
new file mode 100644
index 0000000000000000000000000000000000000000..b2bdec2d71b6a5ce4ae49efc37516809c50e4d5e
--- /dev/null
+++ b/practice/sandbox/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$/../.." vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/practice/sandbox/out/production/sandbox/TypeIntroKt.class b/practice/sandbox/out/production/sandbox/TypeIntroKt.class
index 0bb3babb3cb6b06914a7f1389b60aba6af54f9af..041ca331b86f342f88c7d3422383ccda66443394 100644
Binary files a/practice/sandbox/out/production/sandbox/TypeIntroKt.class and b/practice/sandbox/out/production/sandbox/TypeIntroKt.class differ
diff --git a/practice/sandbox/src/TypeIntro.kt b/practice/sandbox/src/TypeIntro.kt
index 969458a22d25d6e1ce2ca83d055219bd08bf8bf7..034983fa4e652ee98e9479896b8a877312938d32 100644
--- a/practice/sandbox/src/TypeIntro.kt
+++ b/practice/sandbox/src/TypeIntro.kt
@@ -1,4 +1,5 @@
 fun main() {
     var experiencePoints: Int = 5
+    experiencePoints += 5
     println(experiencePoints)
 }
\ No newline at end of file