백준 [ALGORITHM] - 빈도 정렬 (2910)

N, C = map(int, input().split())

num = list(map(int, input().split()))
print_list = list()
hash_map = dict()

for i in range(N):
    if str(num[i]) in hash_map.keys():
        hash_map[str(num[i])][0] += 1
    else:
        hash_map[str(num[i])] = [1, i] 

hash_map = sorted(hash_map.items(), key=lambda x: (x[1][0], -x[1][1]), reverse=True)

for i in range(len(hash_map)):
    #print(hash_map[i][0])
    #print(hash_map[i][1][1])
    print_list.extend(([int(hash_map[i][0])] * int(hash_map[i][1][0])))


str1 = ' '.join(str(s) for s in print_list)
print(str1)

해시맵(dict)를 활용하여 코드 작성함