Given a positive integer n, count the number of sets of positive integers x1<x2<x3<x4 such that:
x1+x2+x3+x4=n
### Input
- A single line containing a positive integer n.
### Output
- Print an integer representing the number of sets.
### Constraints
- 1≤n≤50.
### Example
Input:
10
Output:
1
