Processing math: 100%
Solution - MarisaOJ: Marisa Online Judge

Solution

Time limit: 1000 ms
Memory limit: 256 MB

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