from operator import itemgetter
import sys
input = lambda: sys.stdin.readline().rstrip()
INF = 10**18

N = int(input())
l = []
for i in range(N):
    S = input()
    l.append([S[0],S[-1],S])
l.sort(key=itemgetter(0,1))

ans = 0
last = "a"
for S in l:
    if S[0] < last:
        continue
    for i in range(len(S[2])-1):
        if S[2][i] > S[2][i+1]:
            break
    else:
        ans += len(S[2])
        last = S[1]
print(ans)