n = int(input()) #n组数据测试 for x in range(n): m = int(input()) # 组内有多少数据,对Python来说是费话 a = input().split() #['1', '1', '3' '4','5'] a = [ int(x) for x in a ] mina = min(a) for y in range( a.count(mina)): #把列表中所有的最小值移除 a.remove(mina) if len(a)==0: print("NO") else: print( min(a))