Description

---

You are writing a transcompiler that will be able to translate programs from one programming language to another. Your transcompiler needs to be able to analyze a program to understand what data types it uses and how they should be mapped to the types of the output language.

In order to handle this, you created an inheritance table, which has the following structure:

• derived: a unique data type in the original language;
• base: the base data type from which the derived type is inherited.

It’s guaranteed that there are no cyclic dependencies.

For each translated program a variables table is created, which has the following structure:

• var_name: the unique variable name;
• type: the variable type.

Your task is to write a query that will find the variables of types that are inherited from the Number type. The resulting table should contain var_name and var_type columns and be sorted by var_names.

Example

For the following tables inheritance

derived	base
Double	Number
Int	Number
Int64	Int
Number	Object

and variables

var_name	type
A	Int
B	Object
C	Double
D	Int64
E	Number

the output should be

var_name	var_type
A	Int
C	Double
D	Int64

Type Int64 is inherited from type Int, which in turn is inherited from Number type, so both variables A and D should be included in the result. Double type is also inherited from Number, so C is also present in the resulting table.

• [execution time limit] 10 seconds (mysql)

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/*Please add ; after each select statement*/
CREATE FUNCTION isNumber(class VARCHAR(45))
RETURNS BOOLEAN
BEGIN
    DECLARE basec VARCHAR(45) DEFAULT '';
    DECLARE next VARCHAR(45) DEFAULT NULL;
    DECLARE ret BOOLEAN DEFAULT FALSE;
    DECLARE i INT DEFAULT 0;
    SET next = class;
    SET ret = FALSE;
    SET i = 0;
    WHILE i < 200 AND (NOT ret) AND (SELECT COUNT(base) FROM inheritance WHERE derived = next LIMIT 1) DO
       
        SELECT base INTO basec FROM inheritance WHERE derived = next LIMIT 1;
        SET ret = IF(IFNULL(basec,'') = 'Number', TRUE, FALSE);
        SET next = basec;
        SET i = i+1;
    END WHILE;
    RETURN ret OR i > 100; 
END;
CREATE PROCEDURE typeInheritance()
BEGIN
   	 SELECT var_name, type as var_type FROM variables WHERE isNumber(type) ORDER BY var_name;

END