Problem:


Score : 300 points

Problem Statement

There are N people. The name of the i-th person is S_i.

We would like to choose three people so that the following conditions are met:

The name of every chosen person begins with M, A, R, C or H.

There are no multiple people whose names begin with the same letter.

How many such ways are there to choose three people, disregarding order?

Note that the answer may not fit into a 32-bit integer type.

Constraints

1 \leq N \leq 10^5

S_i consists of uppercase English letters.

1 \leq |S_i| \leq 10

S_i \neq S_j (i \neq j)

Input

Input is given from Standard Input in the following format:

N
S_1
:
S_N

Output

If there are x ways to choose three people so that the given conditions are met, print x.

Sample Input 1

5
MASHIKE
RUMOI
OBIRA
HABORO
HOROKANAI

Sample Output 1

2

We can choose three people with the following names:

MASHIKE, RUMOI, HABORO

MASHIKE, RUMOI, HOROKANAI

Thus, we have two ways.

Sample Input 2

4
ZZ
ZZZ
Z
ZZZZZZZZZZ

Sample Output 2

0

Note that there may be no ways to choose three people so that the given conditions are met.

Sample Input 3

5
CHOKUDAI
RNG
MAKOTO
AOKI
RINGO

Sample Output 3

7



Sample input:
5
MASHIKE
RUMOI
OBIRA
HABORO
HOROKANAI


Sample output:
2

Submission status: Accepted

Solution code:
import itertools
n = int(input())
M = []
A = []
R = []
C = []
H = []
for i in range(n):
    s = str(input())
    if s[0] == "M":
        M.append(s)
    elif s[0] == "A":
        A.append(s)
    elif s[0] == "R":
        R.append(s)
    elif s[0] == "C":
        C.append(s)
    elif s[0] == "H":
        H.append(s)
L = []
if len(M) > 0:
    L.append(M)
if len(A) > 0:
    L.append(A)
if len(R) > 0:
    L.append(R)
if len(C) > 0:
    L.append(C)
if len(H) > 0:
    L.append(H)
ans = 0
for i in itertools.combinations(L, 3):
    #print(i)
    ans += len(i[0])*len(i[1])*len(i[2])

print(ans)

Submission status: Accepted

Solution code:
import itertools
n = int(input())
h_list = []
for i in range(n):
    h_list.append(input()[0])
MARCH = ['M', 'A', 'R', 'C', 'H']
b = []
for a in MARCH:
    b.append(h_list.count(a))
bc = itertools.combinations(b, 3)
count = 0
for v in bc:
    count += v[0] * v[1] * v[2]
print(count)

Submission status: Accepted

Solution code:
n = int(input())
march = [0] * 5
for i in range(n):
    s = input()
    if s[0] == "M":
        march[0] += 1
    elif s[0] == "A":
        march[1] += 1
    elif s[0] == "R":
        march[2] += 1
    elif s[0] == "C":
        march[3] += 1
    elif s[0] == "H":
        march[4] += 1
P = [0, 0, 0, 0, 0, 0, 1, 1, 1, 2]
Q = [1, 1, 1, 2, 2, 3, 2, 2, 3, 3]
R = [2, 3, 4, 3, 4, 4, 3, 4, 4, 4]
res = 0
for i in range(10):
    res += march[P[i]] * march[Q[i]] * march[R[i]]
print(res)

Submission status: Accepted

Solution code:
# -*- coding: utf-8 -*-

import itertools

n = int(input())
s = [[] for _ in range(n)]
for i in range(n):
    s[i] = list(input())

delete = []

for i in range(n):
    if s[i][0] == "M" or s[i][0] == "A" or s[i][0] == "R" or s[i][0] == "C" or s[i][0] == "H":
        pass
    else:
        delete.append(i)

diff = 0
for i in range(len(delete)):
    del s[delete[i] - diff]
    diff += 1

cand = [0,0,0,0,0]
for i in range(len(s)):
    if s[i][0] == "M":
        cand[0] += 1
    if s[i][0] == "A":
        cand[1] += 1
    if s[i][0] == "R":
        cand[2] += 1
    if s[i][0] == "C":
        cand[3] += 1
    if s[i][0] == "H":
        cand[4] += 1

ans = 0

for i in range(5):
    for j in range(5):
        if i == j:
            break
        for k in range(5):
            if i == k:
                break
            if j == k:
                break
            ans += int(cand[i] * cand[j] * cand[k])

print(ans)

Submission status: Accepted

Solution code:
N = int(input())
Sn = [input() for _ in range(N)]

from collections import Counter
c = Counter()
for S in Sn:
    c[S[0]] += 1

t = 0
d = ['M','A','R','C','H']
from itertools import combinations
for combi in combinations(d, 3):
    v = 1
    for k in combi:
        v *= c[k]
    t += v
print(t)

Submission status: Accepted

Solution code:
n = int(input())
c = {"M": 0, "A": 0, "R": 0, "C": 0, "H": 0}
march = "MARCH"

for i in range(0, n):
    s = input()[0]
    if s == "M" or s == "A" or s == "R" or s == "C" or s == "H":
        c[s] += 1

s = 0
for i in range(0, 5):
    for j in range(i + 1, 5):
        for k in range(j + 1, 5):
            s += c[march[i]] * c[march[j]] * c[march[k]]

print(s)

Submission status: Accepted

Solution code:
n = int(input())
li = [input() for _ in range(n)]
march = [0, 0, 0, 0, 0]
for i in range(n):
  if li[i][0] == 'M': march[0] += 1
  if li[i][0] == 'A': march[1] += 1
  if li[i][0] == 'R': march[2] += 1
  if li[i][0] == 'C': march[3] += 1
  if li[i][0] == 'H': march[4] += 1
cnt = 0
for j in range(3):
  for k in range(j+1, 4):
    for l in range(k+1, 5):
      cnt += march[j] * march[k] * march[l]

print(cnt)

Submission status: Accepted

Solution code:
N = int(input())
S = []
for i in range(N):
	S.append(list(input())[0])

count = [0] * 5
for i in range(N):
	if S[i] == "M":
		count[0] += 1
	elif S[i] == "A":
		count[1] += 1
	elif S[i] == "R":
		count[2] += 1
	elif S[i] == "C":
		count[3] += 1
	elif S[i] == "H":
		count[4] += 1
		
sum = 0
for i in range(3):
	sum += count[i] * count[i+1] * count[i+2]

for i in range(2):
	sum += count[i] * count[i+1] * count[i+3]
	sum += count[i] * count[i+2] * count[i+3]

for i in range(3):
		sum += count[0] * count[i+1] * count[4]
print(sum)

Submission status: Accepted

Solution code:
N = int(input())
march = 'MARCH'
l = [0] * len(march)
for i in range(N):
    S = input()
    for j in range(len(march)):
        if S[0] == march[j]:
            l[j] += 1

# print(l)
tmp = []
lenl = len(l)
for i in range(lenl):
    for j in range(i + 1, lenl):
        for k in range(j + 1, lenl):
           tmp.append(l[i]*l[j]*l[k])
# print('tmp',tmp)
print(sum(tmp))

Submission status: Accepted

Solution code:
import sys
input = sys.stdin.readline

N = int(input())
S = [input() for _ in range(N)]
MARCHcnt = [0]*5
ans = 0

for i in S:
    if i[0] == 'M':
        MARCHcnt[0] += 1
    elif i[0] == 'A':
        MARCHcnt[1] += 1
    elif i[0] == 'R':
        MARCHcnt[2] += 1
    elif i[0] == 'C':
        MARCHcnt[3] += 1
    elif i[0] == 'H':
        MARCHcnt[4] += 1

for i in range(3):
    for j in range(i+1, 4):
        for k in range(j+1, 5):
            ans += MARCHcnt[i]*MARCHcnt[j]*MARCHcnt[k]

print(ans)

Submission status: Accepted

Solution code:
import itertools
n = int(input())

counter = {}
for i in range(n):
  head = input()[0]
  if head not in counter:
    counter[head] = 1
  else:
    counter[head] += 1

char_num = 0
char_count = []
for c in "MARCH":
  if c in counter:
    char_num += 1
    char_count.append(counter[c])

ans = 0
if char_num < 3:
  print(0)
else:
  for a, b, c in itertools.combinations(char_count, 3):
    ans += a * b * c
  print(ans)

Submission status: Accepted

Solution code:
n = int(input())
sn = [ input() for i in range(n)]

m, a, r, c, h = 0, 0, 0, 0, 0

for s in sn:
    if s[0] == "M":
        m += 1
    elif s[0] == "A":
        a += 1
    elif s[0] == "R":
        r += 1
    elif s[0] == "C":
        c += 1
    elif s[0] == "H":
        h += 1

print(
    m * a * r
    + m * a * c
    + m * a * h
    + m * r * c
    + m * r * h
    + m * c * h
    + a * r * c
    + a * r * h
    + a * c * h
    + r * c * h)

Submission status: Accepted

Solution code:
n = int(input())
count = [0]*5
for i in range(n):
    s = input()
    if s[0] == "M":
        count[0] += 1
    if s[0] == "A":
        count[1] += 1
    if s[0] == "R":
        count[2] += 1
    if s[0] == "C":
        count[3] += 1
    if s[0] == "H":
        count[4] += 1

ans = 0
for i in range(5):
    for j in range(i+1,5):
        for k in range(j+1,5):
            ans += count[i]*count[j]*count[k]

print(ans)

Submission status: Accepted

Solution code:
n=int(input())
stack=[0,0,0,0,0]
march=["M","A","R","C","H"]
for i in range(n):
  k=input()
  for j in range(5):
    if k[0]==march[j]:
      stack[j]+=1
      break
ans=0
for i in range(3):
  for j in range(i+1,4):
    for k in range(j+1,5):
      ans+=stack[i]*stack[j]*stack[k]
print(ans)

Submission status: Accepted

Solution code:
from collections import Counter
from itertools import combinations


n = int(input())
s = Counter([input()[0] for _ in range(n)])

choices = combinations([x for x in s.keys() if x[0] in 'MARCH'], 3)

if not choices:
    print(0)
    exit()

ans = 0
for choice in choices:
    tmp = 1
    for key in choice:
        tmp *= s[key]
    ans += tmp

print(ans)

Submission status: Accepted

Solution code:
import itertools
N=int(input())
l=[]
for i in range(N):
    s=str(input())
    l.append(s[0])
m=0
a=0
r=0
c=0
h=0
for i in range(N):
    if l[i]=='M':
        m+=1
    elif l[i]=='A':
        a+=1
    elif l[i]=='R':
        r+=1
    elif l[i]=='C':
        c+=1
    elif l[i]=='H':
        h+=1
D=[0]*5
for i in range(5):
    D[0]=m
    D[1]=a
    D[2]=r
    D[3]=c
    D[4]=h

seq=[0,1,2,3,4]
l=list(itertools.combinations(seq,3))
ans=0
for i in range(len(l)):
    a=l[i][0]
    b=l[i][1]
    c=l[i][2]
    ans+=D[a]*D[b]*D[c]
print(ans)

Submission status: Accepted

Solution code:
N = int(input())
l =[0]*5
for i in range(N):
    s = input()
    if s[0] =='M':
        l[0] += 1
    elif s[0] =="A":
        l[1] += 1
    elif s[0] =="R":
        l[2] += 1
    elif s[0] =="C":
        l[3] += 1
    elif s[0] =="H":
        l[4] += 1
print(l[0]*(l[1]*(l[2]+l[3]+l[4]) + l[2]*(l[3]+l[4]) + l[3]*l[4]) +l[1]*(l[2]*(l[3]+l[4])+l[3]*l[4])+l[2]*l[3]*l[4])

Submission status: Accepted

Solution code:
import collections
import itertools
n = int(input())
s = []
for _ in range(n):
    s.append(input())
s = [i[0] for i in s if i[0] in "MARCH"]
l = collections.Counter(s)
c = 0
for i,j,k in itertools.combinations(l.keys(), 3):
    c += l[i]*l[j]*l[k]
print(c)

Submission status: Accepted

Solution code:
N = int(input())

S = []
for i in range(N):
    S.append(input())

A = [0] * 5
for s in S:
    if s[0] is 'M':
        A[0] += 1
    elif s[0] is 'A':
        A[1] += 1
    elif s[0] is 'R':
        A[2] += 1
    elif s[0] is 'C':
        A[3] += 1
    elif s[0] is 'H':
        A[4] += 1

D1 = [0,0,0,0,0,0,1,1,1,2]
D2 = [1,1,1,2,2,3,2,2,3,3]
D3 = [2,3,4,3,4,4,3,4,4,4]

ans = 0
for i in range(10):
    ans += A[D1[i]] * A[D2[i]] * A[D3[i]]

print(ans)

Submission status: Accepted

Solution code:
from itertools import combinations
from collections import defaultdict
n = int(input())

d = defaultdict(int)

for i in range(n):
    d[input()[0]] += 1

w = ['M', 'A', 'R', 'C', 'H']

counter = 0
for w in combinations(w, 3):
    counter += d[w[0]] * d[w[1]] * d[w[2]]

print(counter)

Submission status: Accepted

Solution code:
N = int(input())
S = [input()[0] for i in range(N)]
M = S.count("M")
A = S.count("A")
R = S.count("R")
C = S.count("C")
H = S.count("H")
print(M * (A * (R + C + H) + R * (C + H) + C * H) + A * (R * (C + H) + C * H) + R * C * H)

Submission status: Accepted

Solution code:
import itertools
seq = ('M', 'A', 'R', 'C', 'H')
li = list(itertools.combinations(seq, 3))
MARCH = {'M': 0, 'A': 0, 'R': 0, 'C': 0, 'H':0}
N = int(input())
for i in range(N):
    top = input()[0]
    if top in 'MARCH':
        MARCH[top] += 1
ans = 0
for i in li:
    tmp = 1
    for j in i:
        tmp *= MARCH[j]
    ans += tmp
print(ans)

Submission status: Accepted

Solution code:
import collections
N=int(input())
S=[]
ans=-1
for i in range(N):
    s=input()
    if s[0] in 'MARCH':
        S.append(s[0])
L=list(collections.Counter(S).values())
if len(L)<3:
    ans=0
else:
    R=[L[i]*L[j]*L[k] for i in range(len(L)-2) for j in range(i+1,len(L)-1) for k in range(j+1,len(L))]
    ans=sum(R)
print(ans)

Submission status: Accepted

Solution code:
import math, string, itertools, fractions, heapq, collections, re,  array, bisect, sys, random, time, copy, functools
sys.setrecursionlimit(10**7)
inf = 10 ** 20
eps = 1.0 / 10**10
mod = 10**9+7
dd = [(-1, 0), (0, 1), (1, 0), (0, -1)]
ddn = [(-1, 0), (-1, 1), (0, 1), (1, 1), (1, 0), (1, -1), (0, -1), (-1, -1)]
def LI(): return [int(x) for x in sys.stdin.readline().split()]
def LI_(): return [int(x)-1 for x in sys.stdin.readline().split()]
def LF(): return [float(x) for x in sys.stdin.readline().split()]
def LS(): return sys.stdin.readline().split()
def I(): return int(sys.stdin.readline())
def F(): return float(sys.stdin.readline())
def pf(s): return print(s, flush=True)

N = I()
S = []
for i in range(N):
    S.append(input())
#  N = 10**5
#  S = []
#  for i in range(N):
#      S.append(random.choice(string.ascii_letters))

# count?
"""
countして、かけていく
"""
M, A, R, C, H  = 0,0,0,0,0

for s in S:
    if s[0] == "M":
        M += 1
    elif s[0] == "A":
        A += 1
    elif s[0] == "R":
        R += 1
    elif s[0] == "C":
        C += 1
    elif s[0] == "H":
        H += 1

l = [M,A,R,C,H]
result = 0
for i in range(len(l)-2):
    for j in range(i+1, len(l)-1):
        for k in range(j+1, len(l)):
            result += l[i]*l[j]*l[k]
print(result)

Submission status: Accepted

Solution code:
N= int(input())
S = [input() for _ in range(N)]

cnt = {}

for s in S:
  cnt[s[0]] = cnt.get(s[0], 0) +1

n = [cnt.get(x,0) for x in ['M','A','R','C','H']]

a = sum(n) **3 - 3*sum([v**2 for v in n])*sum(n) + 2*sum([v**3 for v in n])
print(a//6)

Submission status: Accepted

Solution code:
n = int(input())
m = 0
a = 0
r = 0
c = 0
h = 0
ans = 0
for i in range(n):
    s = input()
    if s[0] == 'M':
        m += 1
    elif s[0] == 'A':
        a += 1
    elif s[0] == 'R':
        r += 1
    elif s[0] == 'C':
        c += 1
    elif s[0] == 'H':
        h += 1
lis = [m, a, r, c, h]
for i in range(len(lis) - 2):
    for j in range(i + 1, len(lis) - 1):
        for k in range(j + 1, len(lis)):
            ans += lis[i] * lis[j] * lis[k]
print(ans)

Submission status: Accepted

Solution code:
n = int(input())
s = [list(str(input())) for i in range(n)]
m,a,r,c,h = 0,0,0,0,0
for i in range(n):
    if s[i][0] == "M":
        m = m + 1
    elif s[i][0] == "A":
        a = a + 1
    elif s[i][0] == "R":
        r = r + 1
    elif s[i][0] == "C":
        c = c + 1
    elif s[i][0] == "H":
        h = h + 1

t = [m,a,r,c,h]
p = 0
for i in range(3):
    for j in range(i+1,4):
        for k in range(j+1,5):
            p = p + t[i] * t[j] * t[k]

print(p)

Submission status: Accepted

Solution code:
# /usr/bin/python
# -*- coding: utf-8 -*-
#
import sys
 

Sn = {'M':0,'A':0,'R':0,'C':0,'H':0}
for i in range(int(input())):
  s = str(input())[0]
  if s in Sn:
    Sn[s] += 1

ans = 0
Sn = list(Sn.values())
for i in range(5):
  if Sn[i] == 0:
    continue
  for j in range(i+1,5):
    if Sn[j] == 0:
      continue
    for k in range(j+1,5):
      if Sn[k] == 0:
        continue
      ans += Sn[i]*Sn[j]*Sn[k]

print(ans)

Submission status: Accepted

Solution code:
import itertools
from collections import Counter
n=int(input())
S=[input()[0] for i in range(n)]
ls=["M","A","R","C","H"]
S=Counter([i for i in S if i in ls])
ans=0
for i,j,k in itertools.combinations(ls,3):
  ans+=S[i]*S[j]*S[k]
print(ans)

Submission status: Accepted

Solution code:
N = int(input())
S = [input() for i in range(N)]

M = []
A = []
R = []
C = []
H = []

for i in S:
    if i[0] == "M":
        M.append(i)
    elif i[0] == "A":
        A.append(i)
    elif i[0] == "R":
        R.append(i)
    elif i[0] == "C":
        C.append(i)
    elif i[0] == "H":
        H.append(i)

L = [M,A,R,C,H]
L = list(map(len,L))
ans = 0
for i in range(5):
    for j in range(i+1,5):
        for k in range(j+1,5):
            ans += L[i]*L[j]*L[k]

print(ans)

Submission status: Accepted

Solution code:
MARCH = list("MARCH")
check = set(MARCH)
cand = [0] * 5
N = int(input())
for i in range(N):
    n = list(input())[0]
    for j in range(5):
        if n == MARCH[j]:
            cand[j] += 1

ans = 0
for i in range(5):
    for j in range(i+1, 5):
        for k in range(j+1, 5):
            ans += cand[i] * cand[j] * cand[k]
print(ans)

Submission status: Accepted

Solution code:
import itertools

N = int(input())
S =[0]*N
for i in range(N):
    S[i] = input()

member = {}
for m in ['M', 'A', 'R', 'C', 'H']:
    member[m] = len(list(filter(lambda x: x[0] == m, S)))

#print(member)

ans = 0
for i, j, k in itertools.combinations(['M', 'A', 'R', 'C', 'H'], 3):
    ans += member[i] * member[j] * member[k]

print(ans)

Submission status: Accepted

Solution code:
import sys

N=int(sys.stdin.readline().rstrip())
c={'M':0, 'A':0, 'R':0, 'C':0, 'H':0 }
for i in range(N):
    s=sys.stdin.readline().rstrip()
    try:
        c[s[0]] += 1
    except KeyError:
        c[s[0]] = 1
a='MARCH'
ans=0
for i1 in range(0,5):
    for i2 in range(i1+1,5):
        for i3 in range(i2+1,5):
            ans+=c[a[i1]]*c[a[i2]]*c[a[i3]]
print(ans)

Submission status: Accepted

Solution code:
import itertools
n = int(input())

march = ['M','A','R','C','H']

cnt = [0,0,0,0,0]

for _ in range(n):
    s = input()
    for i in range(5):
        if s[0] == march[i]:
            cnt[i]+=1
            break

b = list(itertools.combinations(cnt,3))

res = 0
for l in b:
    res +=(l[0]*l[1]*l[2])
 
print(res)

Submission status: Accepted

Solution code:
from functools import reduce
from itertools import combinations
from operator import mul


def solve(string):
    n, *s = string.split()
    # num = [len([True for _s in s if _s[0] == _i]) for _i in "M A R C H".split()]
    initial = "MARCH"
    num = [0 for _ in range(6)]
    for _s in s:
        i = initial.find(_s[0])
        num[i] += 1
    return str(sum([reduce(mul, n) for n in combinations(num[:5], 3)]))


if __name__ == '__main__':
    n = int(input())
    print(solve('{}\n'.format(n) + '\n'.join([input() for _ in range(n)])))

Submission status: Accepted

Solution code:
from functools import reduce
from itertools import combinations
from operator import mul


def solve(string):
    n, *s = string.split()
    # num = [len([True for _s in s if _s[0] == _i]) for _i in "M A R C H".split()]
    initial = "MARCH"
    num = [0 for _ in enumerate(initial)]
    for _s in s:
        i = initial.find(_s[0])
        if i < 0:
            continue
        num[i] += 1
    return str(sum([reduce(mul, n) for n in combinations(num, 3)]))


if __name__ == '__main__':
    n = int(input())
    print(solve('{}\n'.format(n) + '\n'.join([input() for _ in range(n)])))

Submission status: Accepted

Solution code:
from functools import reduce
from itertools import combinations
from operator import mul


def solve(string):
    n, *s = string.split()
    num = [len([True for _s in s if _s[0] == _i]) for _i in "M A R C H".split()]
    num = [n for n in num if n > 0]
    return str(sum([reduce(mul, n) for n in combinations(num, 3)]))


if __name__ == '__main__':
    n = int(input())
    print(solve('{}\n'.format(n) + '\n'.join([input() for _ in range(n)])))

Submission status: Accepted

Solution code:
from functools import reduce
from itertools import combinations
from operator import mul


def solve(string):
    n, *s = string.split()
    num = [len([True for _s in s if _s[0] == _i]) for _i in "M A R C H".split()]
    return str(sum([reduce(mul, n) for n in combinations(num, 3)]))


if __name__ == '__main__':
    n = int(input())
    print(solve('{}\n'.format(n) + '\n'.join([input() for _ in range(n)])))

Submission status: Accepted

Solution code:
from functools import reduce
from itertools import combinations
from operator import mul


def solve(string):
    n, *s = string.split()
    num = [len([True for _s in s if _s[0] == _i]) for _i in "M A R C H".split()]
    ans = 0
    for n in combinations(num, 3):
        ans += reduce(mul, n)
    return str(ans)


if __name__ == '__main__':
    n = int(input())
    print(solve('{}\n'.format(n) + '\n'.join([input() for _ in range(n)])))

Submission status: Accepted

Solution code:
def solve(string):
    n, *s = string.split()
    num = [len([True for _s in s if _s[0] == _i]) for _i in "M A R C H".split()]
    ans = 0
    for i in range(5):
        for j in range(i + 1, 5):
            for k in range(j + 1, 5):
                ans += num[i] * num[j] * num[k]
    return str(ans)


if __name__ == '__main__':
    n = int(input())
    print(solve('{}\n'.format(n)+'\n'.join([input() for _ in range(n)])))

Submission status: Accepted

Solution code:
N = int(input())
s = 'MARCH'
c = [0] * 5
for i in range(N):
    S = input()
    for j in range(5):
        if S[0] == s[j]:
            c[j] += 1

ans = 0
for i in range(3):
    for j in range(i + 1, 4):
        for k in range(j + 1, 5):
            ans += c[i] * c[j] * c[k]
print(ans)

Submission status: Accepted

Solution code:
from collections import defaultdict
N = int(input())
S = [input() for _ in range(N)]
d = defaultdict(list)
chars = ["M", "A", "R", "C", "H"]

for s in S:
    c = s[0]
    for cc in chars:
        if c == cc:
            d[c].append(s)
            break
len_list = []
for c in chars:
    l = d[c]
    len_list.append(len(l))

ans = 0
n_arr = [0, 0, 0, 0, 0]
for i in range(1, 32):
    n = i
    count = 0
    for j in range(0, 5):
        if n % 2 > 0:
            count += 1
            n_arr[j] = 1
        else:
            n_arr[j] = 0
        n = n // 2
    if count != 3:
        continue
    c = 1
    for j in range(0, 5):
        if n_arr[j] > 0:
            c *= len_list[j] * n_arr[j]
    ans += c
print(ans)

Submission status: Accepted

Solution code:
from collections import defaultdict
from itertools import permutations, combinations,combinations_with_replacement,product

N = int(input())

ls = ['M', 'A', 'R', 'C', 'H']
d = defaultdict(int)
ans = 0

for i in range(N):
    a = input()
    if a[0] in ls:
        d[a[0]] += 1
        
if len(d) <= 2:
    print(0)
else:
    nl = []
    for j in d.values():
        nl.append(j)
    for x in list(combinations(nl, 3)):
        sum = 1
        for y in x:
            sum *= y
        ans += sum
    print(ans)

Submission status: Accepted

Solution code:
N=int(input())
chars=['M','A','R','C','H']
dict={}
for c in chars:
  dict[c]=0
  
ans=0
  
for i in range(N):
  s=input()
  if (s[0] in chars):
    dict[s[0]]+=1

L=list(dict.values())
    
for i in range(2**5):
  usedchars=[]
  for j in range(5):
    if i>>j&1==1:
      usedchars.append(L[j])
    
  if len(usedchars)==3:
    ans+=usedchars[0]*usedchars[1]*usedchars[2]

print(ans)

Submission status: Accepted

Solution code:
from collections import Counter
from itertools import combinations
march = list("MARCH")
march = dict(zip(march, march))
N = int(input())
S = [march.get(input()[0], -1) for _ in range(N)]
cnt = Counter(S)
ans = 0
for comb in combinations("MARCH", 3):
    tmp = 1
    for c in comb:
        tmp *= cnt[c]
    ans += tmp
print(ans)

Submission status: Accepted

Solution code:
n=int(input())
m=[]
a=[]
r=[]
c=[]
h=[]
for _ in range(n):
    x=input()
    if x[0]=="M":
        m.append(x)
    elif x[0]=="A":
        a.append(x)
    elif x[0]=="R":
        r.append(x)
    elif x[0]=="C":
        c.append(x)
    elif x[0]=="H":
        h.append(x)
l=[len(m),len(a),len(r),len(c),len(h)]
ans=0
for x in range(3):
    for y in range(x+1,4):
        for z in range(y+1,5):
            ans+=l[x]*l[y]*l[z]
print(ans)

Submission status: Accepted

Solution code:
one = {'M':0, 'A':0, 'R':0, 'C':0, 'H':0}
n=int(input())
for i in range(n):
  c=input()[0]
  one[c] = one.get(c,0)+1
m,a,r,c,h=one['M'],one['A'],one['R'],one['C'],one['H']
print(m*a*r+m*a*c+m*a*h+m*r*c+m*r*h+m*c*h+a*r*c+a*r*h+a*c*h+r*c*h)

Submission status: Accepted

Solution code:
N = int(input())
S = ''.join([str(input())[0] for i in range(N)])
count = []
for char in 'MARCH':
    tmp = S.count(char)
    if tmp != 0:
        count.append(tmp)
ans = 0
for i in range(1<<len(count)):
    if bin(i).count('1') == 3:
        tmp = 1
        for j in range(len(count)):
            if i>>j & 1 == 1:
                tmp *= count[j]
        ans += tmp
print(ans)

Submission status: Accepted

Solution code:
N = int(input())
S = [str(input())[0] for i in range(N)]
S = ''.join(S)
count = []
for char in 'MARCH':
    tmp = S.count(char)
    if tmp != 0:
        count.append(tmp)
ans = 0
for i in range(1<<len(count)):
    if bin(i).count('1') == 3:
        tmp = 1
        for j in range(len(count)):
            if i>>j & 1 == 1:
                tmp *= count[j]
        ans += tmp
print(ans)

Submission status: Accepted

Solution code:
from itertools import combinations

MARCH = ['M', 'A', 'R', 'C', 'H']
counts = [0]*5
N = int(input())
for i in range(N):
    head = input()[0]
    if head in MARCH:
        counts[MARCH.index(head)] += 1
alist = [t for t in zip(MARCH, counts) if t[1] != 0]

if len(alist) > 2:
    ans = 0
    for combination in combinations(range(5), 3):
        i, j, k = combination
        ans += counts[i] * counts[j] * counts[k]
    print(ans)
else:
    print(0)

Submission status: Accepted

Solution code:
n = int(input())
S = [input() for i in range(n)]
a = 0
b = 0
c = 0
d = 0
e = 0
for s in S:
    if s[0]=='M':
        a += 1
    elif s[0]=='A':
        b += 1
    elif s[0]=='R':
        c += 1
    elif s[0]=='C':
        d += 1
    elif s[0]=='H':
        e += 1
print(a*b*c+a*b*d+a*b*e+b*c*d+b*c*e+c*d*e+a*c*d+a*c*e+a*d*e+b*d*e)

Submission status: Accepted

Solution code:
import itertools
N = int(input())
numslist = [0,0,0,0,0]
ans=0
for i in range(N):
    head=[j for j in input()][0]
    if head=="M":
        numslist[0]+=1
    elif head=="A":
        numslist[1]+=1
    elif head=="R":
        numslist[2]+=1
    elif head=="C":
        numslist[3]+=1
    elif head=="H":
        numslist[4]+=1
for v in itertools.combinations(numslist, 3):
    ans+=(v[0]*v[1]*v[2])
print(ans)

Submission status: Accepted

Solution code:
# https://atcoder.jp/contests/abc089/tasks/abc089_c

import itertools
import collections
import bisect

def main():
    N = int(input())
    A = {}
    for key in ['M', 'A', 'R', 'C', 'H']:
        A[key] = []
    for _ in range(N):
        a = input()
        if a[0] in ['M', 'A', 'R', 'C', 'H']:
            A[a[0]].append(a)

    # print(A)
    ans = 0

    for c in itertools.combinations(['M', 'A', 'R', 'C', 'H'], 3):
        ans += len(A[c[0]]) * len(A[c[1]]) * len(A[c[2]])

    print(ans)


if __name__ == '__main__':
    main()

Submission status: Accepted

Solution code:
import itertools


def main():
    N = int(input())
    d = {'M': 0, 'A': 0, 'R': 0, 'C': 0, 'H': 0}
    for _ in range(N):
        S = input()
        if S[0] in d:
            d[S[0]] += 1
    print(sum(d[a] * d[b] * d[c]
              for a, b, c in itertools.combinations(d.keys(), 3)))


main()

Submission status: Accepted

Solution code:
import itertools


def main():
    N = int(input())
    d = {'M': 0, 'A': 0, 'R': 0, 'C': 0, 'H': 0}
    for _ in range(N):
        S = input()
        if S[0] in d:
            d[S[0]] += 1
    print(sum(d[a] * d[b] * d[c]
              for a, b, c in list(itertools.combinations(d.keys(), 3))))


main()

Submission status: Accepted

Solution code:
import itertools


def main():
    N = int(input())
    d = {'M': 0, 'A': 0, 'R': 0, 'C': 0, 'H': 0}
    for _ in range(N):
        S = input()
        if S[0] in d:
            d[S[0]] += 1
    ans = 0
    for a, b, c in list(itertools.combinations(d.keys(), 3)):
        ans += d[a] * d[b] * d[c]
    print(ans)


main()

Submission status: Accepted

Solution code:
from itertools import combinations

input = open(0).read

Sn = [i[0] for i in input().split() if i[0] in "MARCH"]
st = set(Sn)


def main():

    print(
        sum(x * y * z for x, y, z
            in combinations([Sn.count(s) for s in st], 3)))

    return


main()

Submission status: Accepted

Solution code:
from itertools import combinations

input = open(0).read

Sn = [i[0] for i in input().split() if i[0] in "MARCH"]


def main():

    print(
        sum(x * y * z for x, y, z
            in combinations([Sn.count(s) for s in "MARCH"], 3)))

    return


main()

Submission status: Accepted

Solution code:
input = open(0).read

N, *Sn = map(str, input().split())
N = int(N)


def main():
    M = {j for j in Sn if j[0] in "M"}
    A = {j for j in Sn if j[0] in "A"}
    R = {j for j in Sn if j[0] in "R"}
    C = {j for j in Sn if j[0] in "C"}
    H = {j for j in Sn if j[0] in "H"}

    m = len(M)
    a = len(A)
    r = len(R)
    c = len(C)
    h = len(H)

    print(
        m * a * r
        + m * a * c
        + m * a * h
        + m * r * c
        + m * r * h
        + m * c * h
        + a * r * c
        + a * r * h
        + a * c * h
        + r * c * h)

    return


main()

Submission status: Accepted

Solution code:
from itertools import combinations
n=int(input())
a=[input() for i in range(n)]
cnt=[0]*5
for ai in a:
    if ai[0]=='M':
        cnt[0]+=1
    if ai[0]=='A':
        cnt[1]+=1
    if ai[0]=='R':
        cnt[2]+=1
    if ai[0]=='C':
        cnt[3]+=1
    if ai[0]=='H':
        cnt[4]+=1
comb=combinations(cnt, 3)
ans=0
for c in comb:
    ans+=c[0]*c[1]*c[2]
print(ans)

Submission status: Accepted

Solution code:
N = int(input())
march = 'MARCH'
S = [0,0,0,0,0]
for i in range(N):
    s = input()
    for j in range(5):
        if s[0] == march[j]:
            S[j] += 1
ans = 0
for i in range(5):
    ans += S[0]*(S[1]*(S[2]+S[3]+S[4])+S[2]*(S[3]+S[4])+S[3]*S[4])
    S[0],S[1],S[2],S[3],S[4] = S[1],S[2],S[3],S[4],0

print(ans)

Submission status: Accepted

Solution code:
def march(N: int, S: list) -> int:
    d = {'M': 0, 'A': 0, 'R': 0, 'C': 0, 'H': 0}
    for s in S:
        k = ''
        if s.startswith('M'):
            k = 'M'
        elif s.startswith('A'):
            k = 'A'
        elif s.startswith('R'):
            k = 'R'
        elif s.startswith('C'):
            k = 'C'
        elif s.startswith('H'):
            k = 'H'
        else:
            continue
        d[k] += 1

    count = 0
    val = list(d.values())
    for i in range(5):
        for j in range(i + 1, 5):
            for k in range(j + 1, 5):
                count += val[i] * val[j] * val[k]

    return count


if __name__ == "__main__":
    N = int(input())
    S = [input() for _ in range(N)]
    ans = march(N, S)
    print(ans)

Submission status: Accepted

Solution code:
from collections import defaultdict
from itertools import combinations
march = ['M','A','R','C','H']
combi = combinations(march,3)
N = int(input())
dic = defaultdict(int)
for i in range(N):
    c = input()[0]
    if c in march:
        dic[c] += 1
ans = 0
for c1,c2,c3 in combi: ans += dic[c1]*dic[c2]*dic[c3]
print(ans)

Submission status: Accepted

Solution code:
# 1行に1つの数字
n = int(input())
a = [input() for i in range(n)]

cnt = [0]*5

for x in a:
    if x[0] == "M": cnt[0] += 1
    if x[0] == "A": cnt[1] += 1
    if x[0] == "R": cnt[2] += 1
    if x[0] == "C": cnt[3] += 1
    if x[0] == "H": cnt[4] += 1
    
count = 0
for i in range(3):
    for j in range(i+1, 4):
        for k in range(j+1,5):
            count += cnt[i]*cnt[j]*cnt[k]

print(count)

Submission status: Accepted

Solution code:
import collections
import itertools
N = int(input())
march = ['M','A','R','C','H'] 
lst = []
count = 0
for _ in range(N):
    s = input()
    if s[0] in march:
        lst.append(s[0])
        
c = collections.Counter(lst)  
lst2 = [ c[i] for i in march]
lst3 = list(itertools.combinations(lst2,3))
for l in lst3:
    count += l[0] * l[1] * l[2]
    
print(count)