There are A red socks, B green socks and C Yellow socks in a dark room. Ashwin wants to find N pairs of matching colored socks from the dark room. Given all A, B and C are even and N ≤ (A+B+C)/2, write a program that outputs how many socks Ashwin would have to draw from the dark room in the worst case, to have exactly N pairs.

  1. Input Format

First line contains three space separated integers: A, B and C.

Second line contains the number of pairs Ashwin wants: N

  1. Output Format

Single line containing a single integer which is the count of socks needed to draw in the worst case

  1. Constraints

0 ≤ A,B,C ≤ 106
0 ≤ N ≤ (A + B + C)/2

  1. Example

Input 1:
2 4 4
Output 1:

Input 2:
2 4 4
Output 2:

Input 3:
2 4 4
Output 3:

We don't do homework. However, if you show us that you have put in serious effort to solve this yourself we are here to offer suggestions when you get stuck.

Please read the Daniweb Posting Rules and Suggestions For Posting Questions.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of 1.21 million developers, IT pros, digital marketers, and technology enthusiasts learning and sharing knowledge.