diff --git a/tests/test_Error.c b/tests/test_Error.c
index ba28ac2..c4afd6d 100644
--- a/tests/test_Error.c
+++ b/tests/test_Error.c
@@ -12,29 +12,39 @@ void test_error()
 	/*arrange*/
 	srand(time(0));
 	int bound = 1000;
-	int val1,val2,val3,val4,val5,val6,val7,val8,val9,val10;
+	int invalidErrorCodes_1[bound];
+	int invalidErrorCodesLarge_2[bound];
+	int invalidErrorCodesLargest_3[bound];
 
-	/*act*/
-	val1 = rand() % 1000 + 1;
-	val2 = rand() % 1000 + 1;
-	val3 = rand() % 1000 + 1;
-	val4 = rand() % 1000 + 1;
-	val5 = rand() % 1000 + 1;
-	val6 = rand() % 1000 + 1;
-	val7 = rand() % 1000 + 1;
-	val8 = rand() % 1000 + 1;
-	val9 = rand() % 1000 + 1;
-	val10 = rand() % 1000 + 1;
+	int validErrorCodeUnsuccessfulLogin[bound];
+	int validErrorCodeMaximumNumberOfAttempts[bound];
+	int validErrorCodeNoMenuEntryForNumber[bound];
 
-	/*assertions*/
-	TEST_ASSERT_EQUAL_INT(0,error(val1));	
-	TEST_ASSERT_EQUAL_INT(0,error(val2));	
-	TEST_ASSERT_EQUAL_INT(0,error(val3));	
-	TEST_ASSERT_EQUAL_INT(0,error(val4));	
-	TEST_ASSERT_EQUAL_INT(0,error(val5));	
-	TEST_ASSERT_EQUAL_INT(0,error(val6));	
-	TEST_ASSERT_EQUAL_INT(0,error(val7));	
-	TEST_ASSERT_EQUAL_INT(0,error(val8));	
-	TEST_ASSERT_EQUAL_INT(0,error(val9));	
-	TEST_ASSERT_EQUAL_INT(0,error(val10));	
+	for(int i=0;i<bound;++i){
+		/*1000 numbers in the range from 1 to 2000 */
+		invalidErrorCodes_1[i] = rand() % 2000 + 1;
+		/*1000 numbers in the range from 1000.000 to 100.999.999*/
+		invalidErrorCodesLarge_2[i] = (rand() % 100000000) + 1000000;
+		/*1000 numbers in the range from 1.000.000.000 to 2.000.000.000*/
+		invalidErrorCodesLargest_3[i] = (rand() % 1000000001) + 1000000000 ;
+		/*1000 times -1 in array*/
+		validErrorCodeUnsuccessfulLogin[i] = -1;
+		/*1000 times -2 in array*/
+		validErrorCodeMaximumNumberOfAttempts[i] = -2;
+		/*1000 times -3 in array*/
+		validErrorCodeNoMenuEntryForNumber[i] = -3;
+	}
+
+	/*act and assertions for invalid error codes*/
+	for(int i=0;i<bound;++i){
+		TEST_ASSERT_EQUAL_INT(0,error(invalidErrorCodes_1[i]));
+		TEST_ASSERT_EQUAL_INT(0,error(invalidErrorCodesLarge_2[i]));
+		TEST_ASSERT_EQUAL_INT(0,error(invalidErrorCodesLargest_3[i]));
+	}
+	/*act and assertions for valid error codes*/
+	for(int i=0;i<bound;++i){
+		TEST_ASSERT_EQUAL_INT(-1, error(validErrorCodeUnsuccessfulLogin[i]));
+		TEST_ASSERT_EQUAL_INT(-2, error(validErrorCodeMaximumNumberOfAttempts[i]));
+		TEST_ASSERT_EQUAL_INT(-3, error(validErrorCodeNoMenuEntryForNumber[i]));
+	}
 }