import sys

sys.setrecursionlimit(50007)
sys.stdin = open('censored.in', 'r')
sys.stdout = open('censored.out', 'w')
#sys.stdin = open('input.txt', 'r')
#sys.stdout = open('output.txt', 'w')

n, m, P = map(int, input().split())

uk = 0

a = input()

alph = dict()

for i in range (len(a)):
    alph[a[i]] = i

MAXN = 1488

nxt = []
p = []
pr = []
go = []
link = []
dp = []
was = []
term = []
g = []

#init
for i in range(MAXN):
    was.append(0)
    nxt.append([])
    go.append([])
    p.append(-1)
    pr.append(-1)
    link.append(-1)
    dp.append([])
    term.append(0)
    g.append([])
    for j in range(107):
        nxt[i].append(-1)
        dp[i].append(0)
        go[i].append(-1)

dp[0][0] = 1

def addstr(s):
    global p, pr, nxt, uk
    cur = 0
    for i in range(len(s)):
        let = alph[s[i]]
        if (nxt[cur][let] == -1):
            uk += 1
            nxt[cur][let] = uk
            p[uk] = cur
            pr[uk] = let
        cur = nxt[cur][let]
    term[cur] = 1

def getsufflink(u):
    global link, p, pr
    if (link[u] == -1):
        if (u == 0 or p[u] == 0):
            link[u] = 0
        else:
            link[u] = getlink(getsufflink(p[u]), pr[u])
    return link[u]

def getlink(u, c):
    global go, nxt
    if (go[u][c] == -1):
        if (nxt[u][c] != -1):
            go[u][c] = nxt[u][c]
        else:
            if (u == 0):
                go[u][c] = 0
            else:
                go[u][c] = getlink(getsufflink(u), c)
    return go[u][c]

def markterminal(u):
    was[u] = 1
    if (term[u] == 0):
        if (was[u] == 0):
            markterminal(getsufflink(u))
        term[u] = term[getsufflink(u)]

for i in range(P):
    s = str(input())
    addstr(s)

link[0] = 0

for i in range(uk + 1):
    if (was[i] == 0):
        markterminal(i)

for i in range(uk + 1):
    if (term[i] == 0):
        for j in range(n):
            to = getlink(i, j)
            if (term[to] == 0):
                g[to].append(i)

for len in range(m):
    for i in range(uk + 1):
        for j in (g[i]):
            dp[i][len + 1] += dp[j][len]

ans = 0
for i in range(uk + 1):
    ans += dp[i][m]

print(ans)