import sys # sys.setrecursionlimit(200005) int1 = lambda x: int(x)-1 pDB = lambda *x: print(*x, end="\n", file=sys.stderr) p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr) def II(): return int(sys.stdin.readline()) def LI(): return list(map(int, sys.stdin.readline().split())) def LLI(rows_number): return [LI() for _ in range(rows_number)] def LI1(): return list(map(int1, sys.stdin.readline().split())) def LLI1(rows_number): return [LI1() for _ in range(rows_number)] def SI(): return sys.stdin.readline().rstrip() dij = [(0, 1), (-1, 0), (0, -1), (1, 0)] # dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)] # inf = (1 << 63)-1 inf = (1 << 31)-1 # md = 10**9+7 md = 998244353 from collections import Counter n = II() ss = [SI() for _ in range(n)] cnt = Counter() for s in ss: cc = list(s) for i in range(len(cc)): cc[i] = "*" t = "".join(cc) cnt[t] += 1 cc[i] = s[i] # pDB(cnt) for s in ss: cc = list(s) ans = 0 for i in range(len(cc)): cc[i] = "*" t = "".join(cc) ans += cnt[t]-1 cc[i] = s[i] # pDB(t,ans) print(ans)