diff --git a/lab-3/main_test.c b/lab-3/main_test.c
index 02dc1c4..1eb729a 100644
--- a/lab-3/main_test.c
+++ b/lab-3/main_test.c
@@ -312,4 +312,273 @@ UTEST(scanner, quadratic) {
     ASSERT_STREQ(tokens[index].p, yytext);
     ++index;
   } while (t != TOKEN_EOF);
+}
+
+UTEST(scanner, sorting) {
+  struct token_st tokens[] = {
+    {TOKEN_IDENTIFICATION, "IDENTIFICATION"},
+    {TOKEN_KEYWORD_DIVISION, "DIVISION"},
+    {TOKEN_DOT, "."},
+    {TOKEN_PROGRAM_ID, "PROGRAM-ID"},
+    {TOKEN_DOT, "."},
+    {TOKEN_IDENT, "sorting"},
+    {TOKEN_DOT, "."},
+    {TOKEN_KEYWORD_DATA, "DATA"},
+    {TOKEN_KEYWORD_DIVISION, "DIVISION"},
+    {TOKEN_DOT, "."},
+    {TOKEN_WORKING_STORAGE, "WORKING-STORAGE"},
+    {TOKEN_KEYWORD_SECTION, "SECTION"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "01"},
+    {TOKEN_IDENT, "WS-SORT-AREA"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "05"},
+    {TOKEN_IDENT, "WS-SORT-TABLE"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "10"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_PICTURE, "PIC"},
+    {TOKEN_ALPHANUMERIC, "X"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "10"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_KEYWORD_OCCURS, "OCCURS"},
+    {TOKEN_INTEGER, "100"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "05"},
+    {TOKEN_IDENT, "WS-TEMP-ROW"},
+    {TOKEN_PICTURE, "PIC"},
+    {TOKEN_ALPHANUMERIC, "X"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "10"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "05"},
+    {TOKEN_IDENT, "WS-ROW-MAX"},
+    {TOKEN_PICTURE, "PIC"},
+    {TOKEN_SIGNED_NUMERIC, "S9"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "4"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_COMPUTATION_LEVEL_0, "COMP"},
+    {TOKEN_KEYWORD_VALUE, "VALUE"},
+    {TOKEN_INTEGER, "100"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "05"},
+    {TOKEN_IDENT, "WS-SORT-MAX"},
+    {TOKEN_PICTURE, "PIC"},
+    {TOKEN_SIGNED_NUMERIC, "S9"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "4"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_COMPUTATION_LEVEL_0, "COMP"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "05"},
+    {TOKEN_IDENT, "WS-I"},
+    {TOKEN_PICTURE, "PIC"},
+    {TOKEN_SIGNED_NUMERIC, "S9"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "4"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_COMPUTATION_LEVEL_0, "COMP"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "05"},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_PICTURE, "PIC"},
+    {TOKEN_SIGNED_NUMERIC, "S9"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "4"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_COMPUTATION_LEVEL_0, "COMP"},
+    {TOKEN_DOT, "."},
+    {TOKEN_INTEGER, "05"},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_PICTURE, "PIC"},
+    {TOKEN_SIGNED_NUMERIC, "S9"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "4"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_COMPUTATION_LEVEL_0, "COMP"},
+    {TOKEN_DOT, "."},
+    {TOKEN_PROCEDURE, "PROCEDURE"},
+    {TOKEN_KEYWORD_DIVISION, "DIVISION"},
+    {TOKEN_DOT, "."},
+    {TOKEN_COMMENT, "*> Initialize test data"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_STRING, "\"30\""},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_STRING, "\"10\""},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "2"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_STRING, "\"50\""},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},  
+    {TOKEN_INTEGER, "3"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_STRING, "\"20\""},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "4"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_STRING, "\"40\""},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_INTEGER, "5"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_INTEGER, "5"},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-SORT-MAX"},
+    {TOKEN_COMMENT, "*> * Display original array"},
+    {TOKEN_DISPLAY, "DISPLAY"},
+    {TOKEN_STRING, "\"Original Array Contents:\""},
+    {TOKEN_DISPLAY, "DISPLAY"},
+    {TOKEN_STRING, "\"---------------------\""},
+    {TOKEN_PERFORM, "PERFORM"},
+    {TOKEN_VARYING, "VARYING"},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_KEYWORD_FROM, "FROM"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_KEYWORD_BY, "BY"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_UNTIL, "UNTIL"},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_GREATER_THAN, ">"},
+    {TOKEN_IDENT, "WS-SORT-MAX"},
+    {TOKEN_DISPLAY, "DISPLAY"},
+    {TOKEN_STRING, "\"Element \""},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_STRING, "\": \""},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_END_PERFORM, "END-PERFORM"},
+    {TOKEN_DISPLAY, "DISPLAY"},
+    {TOKEN_SPACE, "SPACE"},
+    {TOKEN_COMMENT, "*> * Simplified bubble sort"},
+    {TOKEN_PERFORM, "PERFORM"},
+    {TOKEN_VARYING, "VARYING"},
+    {TOKEN_IDENT, "WS-I"},
+    {TOKEN_KEYWORD_FROM, "FROM"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_KEYWORD_BY, "BY"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_UNTIL, "UNTIL"},
+    {TOKEN_IDENT, "WS-I"},
+    {TOKEN_GREATER_THAN, ">"},
+    {TOKEN_IDENT, "WS-SORT-MAX"},
+    {TOKEN_SUB, "-"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_PERFORM, "PERFORM"},
+    {TOKEN_VARYING, "VARYING"},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_KEYWORD_FROM, "FROM"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_KEYWORD_BY, "BY"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_UNTIL, "UNTIL"},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_GREATER_THAN, ">"},
+    {TOKEN_IDENT, "WS-SORT-MAX"},
+    {TOKEN_SUB, "-"},
+    {TOKEN_IDENT, "WS-I"},
+    {TOKEN_IF, "IF"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_GREATER_THAN, ">"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_ADD, "+"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-TEMP-ROW"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_ADD, "+"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_MOVE, "MOVE"},
+    {TOKEN_IDENT, "WS-TEMP-ROW"},
+    {TOKEN_KEYWORD_TO, "TO"},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_IDENT, "WS-J"},
+    {TOKEN_ADD, "+"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_END_IF, "END-IF"},
+    {TOKEN_END_PERFORM, "END-PERFORM"},
+    {TOKEN_END_PERFORM, "END-PERFORM"},
+    {TOKEN_COMMENT, "*> * Display sorted array"},
+    {TOKEN_DISPLAY, "DISPLAY"},
+    {TOKEN_STRING, "\"Sorted Array Contents:\""},
+    {TOKEN_DISPLAY, "DISPLAY"},
+    {TOKEN_STRING, "\"--------------------\""},
+    {TOKEN_PERFORM, "PERFORM"},
+    {TOKEN_VARYING, "VARYING"},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_KEYWORD_FROM, "FROM"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_KEYWORD_BY, "BY"},
+    {TOKEN_INTEGER, "1"},
+    {TOKEN_UNTIL, "UNTIL"},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_GREATER_THAN, ">"},
+    {TOKEN_IDENT, "WS-SORT-MAX"},
+    {TOKEN_DISPLAY, "DISPLAY"},
+    {TOKEN_STRING, "\"Element \""},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_STRING, "\": \""},
+    {TOKEN_IDENT, "WS-SORT-ROW"},
+    {TOKEN_LEFT_PARENTHESIS, "("},
+    {TOKEN_IDENT, "WS-INDEX"},
+    {TOKEN_RIGHT_PARENTHESIS, ")"},
+    {TOKEN_END_PERFORM, "END-PERFORM"},
+    {TOKEN_DOT, "."},
+    {TOKEN_STOP, "STOP"},
+    {TOKEN_RUN, "RUN"},
+    {TOKEN_DOT, "."},
+    {TOKEN_EOF, ""},
+  };
+  yyin = fopen("samples/sorting-snippet.cbl", "r");
+  ASSERT_TRUE(yyin);
+  int index = 0;
+  token_t t;
+  do {
+    printf("index: %d token: %d text: %s\n", index, t, yytext);
+    ASSERT_EQ(tokens[index].t, (t = yylex()));
+    ASSERT_STREQ(tokens[index].p, yytext);
+    ++index;
+  } while (t != TOKEN_EOF);
 }
\ No newline at end of file
diff --git a/lab-4/main_test.c b/lab-4/main_test.c
index de1f347..29f238e 100644
--- a/lab-4/main_test.c
+++ b/lab-4/main_test.c
@@ -107,6 +107,32 @@ UTEST(parser, boolean) {
 
   yy_delete_buffer(buffer);
 
+  // Assert the result to test correctness
+  ASSERT_EQ(result, 0);
+}
+
+UTEST(parser, looping) {
+  char string[] = "PERFORM VARYING I FROM 1 BY 1 UNTIL I > 10 MOVE I TO A(I)\0"; 
+  YY_BUFFER_STATE buffer = yy_scan_buffer(string, sizeof(string));
+
+  yylineno = 1;
+  int result = yyparse();
+
+  yy_delete_buffer(buffer);
+
+  // Assert the result to test correctness
+  ASSERT_EQ(result, 0);
+}
+
+UTEST(parser, sorting) {
+  // Read sample file as input
+  yyin = fopen("samples/sorting-snippet.cbl", "r");
+  yyrestart(yyin);
+  ASSERT_TRUE(yyin);
+
+  yylineno = 1;
+  int result = yyparse();
+
   // Assert the result to test correctness
   ASSERT_EQ(result, 0); 
-} 
+}