def a():

    n=int(eval(input()))

    w=list()

    for i in range(n):

        z=eval(input())

        w.append(z)

    for i in range(1,n):

        if w[i][0]!=w[i-1][len(w[i-1])-1]:

            print("No")

            return 0

    w.sort()

    for i in range(n-1):

        if w[i]==w[i+1]:

            print("No")

            return 0

    print("Yes")

    return 0

a()
n=int(eval(input()))

x=[]

f_l_checker=True

x.append(eval(input()))

for i in range(1,n):

    x.append(eval(input()))

    if f_l_checker:

        if x[i][0]==x[i-1][-1]:

            for j in range(i):

                if x[i]==x[j]:

                    f_l_checker=False

        else:

            f_l_checker=False

if f_l_checker:

    print('Yes')

else:

    print('No')
def a():
    n = int(eval(input()))
    w = list()
    for i in range(n):
        z = eval(input())
        w.append(z)
    for i in range(1, n):
        if w[i][0] != w[i - 1][len(w[i - 1]) - 1]:
            print("No")
            return 0
    w.sort()
    for i in range(n - 1):
        if w[i] == w[i + 1]:
            print("No")
            return 0
    print("Yes")
    return 0


a()

n = int(eval(input()))
x = []
f_l_checker = True
x.append(eval(input()))
for i in range(1, n):
    x.append(eval(input()))
    if f_l_checker:
        if x[i][0] == x[i - 1][-1]:
            for j in range(i):
                if x[i] == x[j]:
                    f_l_checker = False
        else:
            f_l_checker = False
if f_l_checker:
    print("Yes")
else:
    print("No")

-def a(): -    n = int(eval(input())) -    w = list() -    for i in range(n): -        z = eval(input()) -        w.append(z) -    for i in range(1, n): -        if w[i][0] != w[i - 1][len(w[i - 1]) - 1]: -            print("No") -            return 0 -    w.sort() -    for i in range(n - 1): -        if w[i] == w[i + 1]: -            print("No") -            return 0 +n = int(eval(input())) +x = [] +f_l_checker = True +x.append(eval(input())) +for i in range(1, n): +    x.append(eval(input())) +    if f_l_checker: +        if x[i][0] == x[i - 1][-1]: +            for j in range(i): +                if x[i] == x[j]: +                    f_l_checker = False +        else: +            f_l_checker = False +if f_l_checker: -    return 0 - - -a() +else: +    print("No")