[python] 백준 1862 미터계

https://www.acmicpc.net/problem/1862

1862번: 미터계

 

# 시간초과

- 1부터 직접 계산

n = int(input())
data = [0]
result = 0
for i in range(1, n+1):
    result += 1
    for j in range(len(str(result))):
        if str(result)[j] == '4':
            result += 10 ** (len(str(result))-j-1)
    data.append(result)
print(data.index(n))

 

# 찾아봄

n = int(input())
result = 0
for i in range(len(str(n))):
    d = n%10
    n = n//10
    
    if d > 4:
        result += (d-1) * (9**i)
    else:
        result += d * (9**i)
print(result)

- 9진법..?