Problem:
Score : 300 points

Problem Statement

You are given an integer N. Among the integers between 1 and N (inclusive), how many Shichi-Go-San numbers (literally "Seven-Five-Three numbers") are there?

Here, a Shichi-Go-San number is a positive integer that satisfies the following condition:

When the number is written in base ten, each of the digits 7, 5 and 3 appears at least once, and the other digits never appear.

Constraints

1 \leq N < 10^9

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

Print the number of the Shichi-Go-San numbers between 1 and N (inclusive).

Sample Input 1

575

Sample Output 1

4

There are four Shichi-Go-San numbers not greater than 575: 357, 375, 537 and 573.

Sample Input 2

3600

Sample Output 2

13

There are 13 Shichi-Go-San numbers not greater than 3600: the above four numbers, 735, 753, 3357, 3375, 3537, 3557, 3573, 3575 and 3577.

Sample Input 3

999999999

Sample Output 3

26484

Solution in Python (3.4.3) (judge verdict: Accepted)

S = input()

'''
357 375 537 573 735 753 
3357 3375 3537 3573 3735 3753 
5357 5375 5537 5573 5735 5753 
3357,3375,3537,

3けた　、4けた 5 ,6, 7, 8
6,18,54,162,486, 8
sum = [2 * 3,2 * 3 * 3,]
'''

N = len(S)
list375 =['3','5','7']
if N <  3:
    print(0)
    exit(0)

for i in range(N + 1):
    if i ==0:
        continue
    else:
        targetList = list375[:]
        for l in targetList:
            #print(l)
            list375.append(l + '3')
            list375.append(l + '5')
            list375.append(l + '7')

result = [i for i in list(set(list375)) if int(i) <= int(S) and (i.count('3') >0 and i.count('5') >0 and i.count('7') >0)]
#print(result)
print(len(result))


'''
def judge753():
    if keta[0] < 3:
        return 0
    if keta[0] < 5:
        if keta[1] < 3:
            return 0
        if keta[1] < 5:
            if keta[2] < 5:
                return 0
            if keta[2] < 7:
                return 1
            return 2
        if keta[1] < 7:
            
        return sum[len(S)-1]
    if keta[0] < 7:
        if keta[1] < 3:
            return sum[len(S)-1] + sum[len(S)-2]
        if keta[1] < 5:
            if keta[2] < 5:
        
        return sum[len(S)-1]
        
print(min(absList))
'''