UDF for Checking 2 values and building context

Hi,

I need to check whether the value in first argument is same as in 2nd Argument, if so then pass that value else add context change.

I am using below UDF for the same

int i=0,j=0;

  for(i=0;i<a.length;i++){

  for(j=0;j<b.length;j++)

    if(a[i].equals(b[j]))

    result.addValue("He");

      else

    result.addContextChange();

  }

A          B

123     234

456     456

789

234

678

Output should be

[]

456

[]

234

[]

Appreciate your help.

Thanks,

CH..