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Let $f$ and $g$ be two nonconstant meromorphic functions defined in  the whole complex plane $\mathbb{C}$.Let $S$ be a set of distinct elements of $\mathbb{C}\cup\{\infty\}$ and $E_{f}(S)=\bigcup_{a\in S}\{z:f(z)-a=0\}$, where each zero is counted according to its multiplicity.  In 1976F.Gross [2] raised the following question:  Can one find finite sets$S_{j}$,$j=1,2$ such that any two nonconstant entire functions $f$and $g$ satisfying $E_{f}(S_{j})=E_{g}(S_{j})$ for $j=1,2$ must beidentical?  To deal with the above question Lahiri[3] employed thenotion of weighted sharing and proved a theorem improving previous results. Very recently Banerjee-Majumder-Mukherjee[1] proved a theorem which improved the result of Lahiri as well as Banerjee. In this improvement however they used the set $S$\, shared by $f$ and $g$ with at least 6 elements. In this paper we reduce the cardinality of $S$ to 4 and obtain their result under weaker condition.

Meromorphic functions, uniqueness