diff --git a/labs/04/lex._an_04.c b/labs/04/lex._an_04.c
new file mode 100644
index 0000000..428597a
--- /dev/null
+++ b/labs/04/lex._an_04.c
@@ -0,0 +1,27 @@
+%{
+#include <stdio.h>
+%}
+    
+%option noyywrap
+    
+%%
+    
+\/{2}*              { printf("COMMENT "); }
+"f"                 { printf("floatdcl "); }
+"i"                 { printf("intdcl "); }
+"p"                 { printf("print "); }
+[a-zA-Z]            { printf("id"); }
+"="                 { printf("assign "); }
+"+"                 { printf("plus "); }
+[0-9]+\.[0-9]+      { printf("fnum "); }
+[0-9]+              { printf("inum "); }
+    
+
+    
+%%
+    
+int main() {
+    yylex();
+    return 0;
+}
+    
\ No newline at end of file
diff --git a/labs/04/testing.txt b/labs/04/testing.txt
new file mode 100644
index 0000000..1d181b7
--- /dev/null
+++ b/labs/04/testing.txt
@@ -0,0 +1,16 @@
+// basic code
+
+//float b
+f b
+
+// integer a
+i a
+
+// a = 5
+a = 5
+
+// b = a + 3.2
+b = a + 3.2
+
+//print 8.5
+p b