Good Fours and Good Fives

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Time limit1sMemory limit1024 MB

Summary

Count the number of unordered ways to write N as a sum of 4s and 5s, or output 0 if no such sum exists.

Level: Easy3 of 10
Topics: Math, Brute force, Implementation
Solved: No attempts yet

Problem

Finn loves Fours and Fives. In fact, he loves them so much that he wants to know the number of ways a number can be formed by using a sum of fours and fives, where the order of the fours and fives does not matter. If Finn wants to form the number 14, there is one way to do this which is 14 = 4 + 5 + 5. As another example, if Finn wants to form the number 20, this can be done two ways, which are 20 = 4 + 4 + 4 + 4 + 4 and 20 = 5 + 5 + 5 + 5. As a final example, Finn can form the number 40 in three ways: 40 = 4+4+4+4+4+4+4+4+4+4, 40 = 4 + 4 + 4 + 4 + 4 + 5 + 5 + 5 + 5, and 40 = 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5.

Your task is to help Finn determine the number of ways that a number can be written as a sum of fours and fives.

Input

The input consists of one line containing a number N.

Output

Output the number of unordered sums of fours and fives which form the number N. Output 0 if there are no such sums of fours and fives.

Examples3

Example 1
Input
```
14
```
Expected output
```
1
```
Example 2
Input
```
40
```
Expected output
```
3
```
Example 3
Input
```
6
```
Expected output
```
0
```