inp = input()mii = lambda : [*map(int,inp().split())]def diff(a, b, ln): return sum(1 for i in range(ln) if a[i] != b[i])def solve(): n, b = mii() l = [inp() for _ in range(n)] r = inp() return min([diff(i, r, b) for i in l])if __name__ == "__main__": tc = ii() for t in range(1, tc+1): ret = solve() print(f"Data Set {t}:\n{ret}\n")