QBASIC Program to calculate loss or profit percentage

Q. Write a QBasic program using user defined function pp(sp,cp) to input selling price and cost price in parameter. then calculate profit or loss percentage. use the function to return the profit pr loss percentage.

DECLARE FUNCTION PP(SP,CP)
CLS
INPUT "ENTER SELLING PRICE"; SP
INPUT "ENTER COST PRICE"; CP
PL= PP(SP, CP)
END

FUNCTION PP (SP, CP)
IF SP > CP THEN
    P = ((SP - CP)) / CP * 100
    PRINT "PROFIT PERCENTAGE="; P
ELSE
    L = ((CP - SP)) / CP * 100
    PRINT "LOSS PERCENTAGE="; L
END IF
END FUNCTION