import sys
import math
import copy
import heapq
from functools import cmp_to_key
from bisect import bisect_left, bisect_right
from collections import defaultdict, deque, Counter
sys.setrecursionlimit(1000000)

# input aliases
input = sys.stdin.readline
getS = lambda: input().strip()
getN = lambda: int(input())
getList = lambda: list(map(int, input().split()))
getZList = lambda: [int(x) - 1 for x in input().split()]

INF = float("inf")
MOD = 10**9 + 7
divide = lambda x: pow(x, MOD-2, MOD)

def nck(n, k, kaijyo):
    return (npk(n, k, kaijyo) * divide(kaijyo[k])) % MOD

def npk(n, k, kaijyo):
    if k == 0 or k == n:
        return n % MOD
    return (kaijyo[n] * divide(kaijyo[n-k])) % MOD

def fact_and_inv(SIZE):
    inv = [0] * SIZE  # inv[j] = j^{-1} mod MOD
    fac = [0] * SIZE  # fac[j] = j! mod MOD
    finv = [0] * SIZE  # finv[j] = (j!)^{-1} mod MOD
    inv[1] = 1
    fac[0] = fac[1] = 1
    finv[0] = finv[1] = 1
    for i in range(2, SIZE):
        inv[i] = MOD - (MOD // i) * inv[MOD % i] % MOD
        fac[i] = fac[i - 1] * i % MOD
        finv[i] = finv[i - 1] * inv[i] % MOD

    return fac, finv

def renritsu(A, Y):
    # example 2x + y = 3, x + 3y = 4
    # A = [[2,1], [1,3]])
    # Y = [[3],[4]] または [3,4]
    A = np.matrix(A)
    Y = np.matrix(Y)
    Y = np.reshape(Y, (-1, 1))
    X = np.linalg.solve(A, Y)

    # [1.0, 1.0]
    return X.flatten().tolist()[0]

class TwoDimGrid:
    # 2次元座標 -> 1次元
    def __init__(self, h, w, wall="#"):
        self.h = h
        self.w = w
        self.size = (h+2) * (w+2)
        self.wall = wall
        self.get_grid()
        # self.init_cost()

    def get_grid(self):
        grid = [self.wall * (self.w + 2)]
        for i in range(self.h):
            grid.append(self.wall + getS() + self.wall)

        grid.append(self.wall * (self.w + 2))
        self.grid = grid
    def init_cost(self):
        self.cost = [INF] * self.size

    def pos(self, x, y):
        # 壁も含めて0-indexed 元々の座標だけ考えると1-indexed
        return y * (self.w + 2) + x
    def getgrid(self, x, y):
        return self.grid[y][x]
    def get(self, x, y):
        return self.cost[self.pos(x, y)]
    def set(self, x, y, v):
        self.cost[self.pos(x, y)] = v
        return
    def show(self):
        for i in range(self.h+2):
            print(self.cost[(self.w + 2) * i:(self.w + 2) * (i+1)])
    def showsome(self, tgt):
        for t in tgt:
            print(t)
        return
    def showsomejoin(self, tgt):
        for t in tgt:
            print("".join(t))
        return

    def search(self):
        grid = self.grid
        move = [(0, 1), (0, -1), (1, 0), (-1, 0)]
        move_eight = [(0, 1), (0, -1), (1, 0), (-1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
        # for i in range(1, self.h+1):
        #     for j in range(1, self.w+1):
        #         cx, cy = j, i
        #         for dx, dy in move_eight:
        #             nx, ny = dx + cx, dy + cy
def getc():
    a = ord("a")
    ret = dict()
    for i in range(1, 27):
        ret[chr(a - 1 + i)] = i
    # print(ret)
    return ret

def solve():
    MOD = 67280421310721
    # a = ["a", "z", "za", "aza"]
    # a.sort()
    # pritn(a)
    n = getN()
    lis = []
    for i in range(n):
        S = list(getS())
        S.reverse()
        lis.append(S)


    lis.sort(key=lambda x: len(x))
    # lis.sort()
    # print(lis)
    ans = 0
    single = dict()
    hash = dict()
    cd = getc()
    for s in lis:
        if len(s) == 1:
            single[s[0]] = 1
            continue
        base = 27
        tmp = 0
        hakken = defaultdict(int)
        singlec = copy.deepcopy(single)
        for c in s[:-1]:
            if c in hakken:
                ans += hakken[c]
                del hakken[c]
            if c in singlec:
                ans += singlec[c]
                del singlec[c]

            tmp = tmp + (base * cd[c]) % MOD
            # tmp %= MOD
            base = (base * 27) % MOD
            # base %= MOD
            if tmp in hash:
                for tgt in hash[tmp]:
                    hakken[tgt] += 1


        if s[-1] in hakken:
            ans += hakken[s[-1]]
        if s[-1] in singlec:
            ans +=singlec[s[-1]]

        if tmp in hash:
            hash[tmp].append(s[-1])
        else:
            hash[tmp] = [s[-1]]
        # print(ans, s, single)

    print(ans)







def main():
    n = getN()
    for _ in range(n):
        solve()

    return
if __name__ == "__main__":
    # main()
    solve()

Measured memory_bytes: 171952