CLEAR CONTENTS IN CELL OF COLUMN A IF CELL IN COLUMN B OR C IS EMPTY

I want to create macros or formula in excel office 2010. If cell in column B or column C is empty, then clear contents in column A. If cell in column B or column C is not empty, then don't clear contents in A. I have a table with range from A1 to C10 and I want to check value at cell B1:B10 and C1:C10. I find that formula: =IF(ISBLANK(B1);"";"YOUR VALUE HERE"), but when I try to use it I have this problem: when is false, content in A1 is change of 0. Thank you in advance!