Fortran: using IF test for matching values between two arrays

I need to use an IF test to determine whether an integer in an array (A) matches with an integer in another array (B) before proceeding with the code. The arrays are of unequal length and contain unique values which are all positive.

I know I can find matching values using:

DO I = 1,SIZE(A)
Match(J)=(ANY(A(I)==B))

However this format isn't accepted by the IF...THEN test. I've not yet found a way to implement it looking online and general testing. What am I missing here?

Appreciate any help!