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Numbers on TreeEvlampiy was gifted a rooted tree. The vertices of the tree are numbered from 1 to n. Each of its vertices also has an integer ai written on it. For each vertex i, Evlampiy calculated ci — the number of vertices j in the subtree of vertex i

F. Spy-stringYou are given n strings a1,a2,…,an: all of them have the same length m. The strings consist of lowercase English letters.Find any string s of length m such that each of the given n strings differs from s in at most one position. Formally, fo