diff --git a/labs/04/lex_analyzer.l b/labs/04/lex_analyzer.l
new file mode 100644
index 0000000..2d937a1
--- /dev/null
+++ b/labs/04/lex_analyzer.l
@@ -0,0 +1,37 @@
+%{
+#include <studio.h>
+%}
+
+letter          [a-eg-hj-op-zA-EG-HJ-OP-Z]
+digit           [0-9]
+integer         {digit}+
+float           (0|[1-9]{digit}*)\.({digit}*[1-9]|0)
+id              {letter}({letter}|{digit})*
+
+%%
+^i              {printf("int10");}
+^f              {printf("float10");}
+^p              {printf("print");}
+\=              {printf("equals");}
+\-              {printf("substract");}
+\+              {printf("add");}
+\*              {printf("multiply");}
+\/              {printf("divide");}
+\(              {printf("open_parenthesis");}
+\)              {printf("close_parenthesis");}
+\{              {printf("open_brace");}
+\}              {printf("close_brace");}
+\[              {printf("open_bracket");}
+\]              {printf("close_bracket");}
+\?              {printf("question_mark");}
+\!              {printf("exclamation_mark");}
+{id}            {printf("id");}
+{integer}       {printf("int");}
+{float}         {printf("float");}
+%%
+
+int main(){
+    yylex();
+
+    return 0;
+}