Rewrite the following algorithm using pseudocode.
FUNCTION simpleSum(n: INTEGER) 
    // declares variables 
    DECLARE sum, number : INTEGER 

    // sets initial values to 0 
    SET sum = 0 
    SET number = 0 

    // loop until n is reached 
    WHILE number < n DO
        SET sum = sum + number 
        SET number = number + 1 
    END WHILE 

    // returns the sum
    RETURN sum 
END FUNCTION