N=int(input())
A=[0 for i in range(12)]
E=["ne","ushi","tora","u","tatsu","mi","uma","hitsuji","saru","tori","inu","i"]
for i in range(N):
    a=input()
    for j in range(12):
        if a==E[j]:
            A[j]+=1
M=max(A)
S=sum(A)-M

if M>(S+1):
    print("NO")
else:
    print("YES")