N = int(input()) S = [] candi = set() for _ in range(N): s=input() candi.add(s) s = ["n","b","m","g","r"] b = ["i","a","a","e","u","u"] s5=[] b6=[] for i in range(6): if i<5: s5.append(i) b6.append(i) import itertools ss = list(itertools.permutations(s5,5)) bb = list(itertools.permutations(b6,6)) #print(ss) flag=False for i in ss: c = [[] for _ in range(16)] #print(c[0]) #print(s[i[0]]) for j in bb: c[1] = (s[i[0]]) c[4] = (s[i[1]]) c[7] = (s[i[2]]) c[10] = (s[i[3]]) c[13] = (s[i[4]]) c[2] = (b[j[0]]) c[5] = (b[j[1]]) c[8] = (b[j[2]]) c[11] = (b[j[3]]) c[14] = (b[j[4]]) cc=c.copy() for k in range(0,16,3): cc[k]=b[j[5]] candidate = "" #print(cc) for ccc in cc: if not ccc==[]: #print(ccc) candidate+=ccc if candidate not in candi: print(candidate) exit() print("No")