text: public ValueEval Evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0){int rnum;if (arg0 is AreaEval){rnum = ((AreaEval)arg0).FirstColumn;}else if (arg0 is RefEval){rnum = ((RefEval)arg0).Column;}else{return ErrorEval.VALUE_INVALID;}return new NumberEval(rnum + 1);}