@DurgaDevikaV  are  your logic inputs only allowing AND ??? or are you handling any valid logic expression,  (In which case would example A AND  (B OR C) AND ( NOT B OR D) would allow for B to be there twice ?)  I wonder if you can find any tools in the handling of report definition logic entry that you could leverage.  Though your use case seems to be more restricted, as report definition allow for A and !A which you don't seem to want.

@DurgaDevikaV

If i understood you requirement correctly then you need to validate if the user has not entered same value multiple times.

Whatever the scenario you want to handle i think you can use edit input to write a custom java code to validate if the same value has been used multiple times or not. For this you will have to split the string in the code and then use nested loop to check if the particular value has already been used or not (this edit input can be written to handle the scenario where the values need to be checked only against a particular AND and OR or it can be used to check if simply there are multiple occurrence of this value or not).

Thank You every one who posted their solutions here. I did it using DT and activity.Used Delimiter method to separate every label and condition in pagelist and stored in to Valuelist(Replaced spaces with $ and given / as escape character in delimiter rule).In loop checked both pagelist and valuelist where label presence happens,inserting query in the place of label.when label presence is true adding that label another valuelist and if already label is existed,then throwing validation error.