Number of Shiba Inus

　

At Izua Park, many people come to walk with their Shiba Inu in the evening. Depending on the color of their hair, there are different types of Shiba Inu: Aka Shiba, Kuro Shiba, Shiro Shiba, and Goma Shiba. Tomoe, who is happy to see so many Shiba Inus around, tried her best to count how many Shiba Inus of each color there was.

Given the number of Shiba Inus of each hair color, write a program that calculates the total number of Shiba Inus.

Input

The input is given in the following format.

  $R$ $B$ $W$ $G$

The number of Aka Shiba $R$ ($1 \leq R \leq 100$), the number of Kuro Shiba $B$ ($1 \leq B \leq 100$), the number of Shiro Shiba $W$ ($1 \leq W \leq 100$), the number of Goma Shiba $G$ ($1 \leq G \leq 100$) are given on one line.

Output

Print the total number of Shiba Inus in one line.

Sample Input and Output

Sample Input 1

4 2 1 1

Sample Output 1

8

Sample Input 2

22 18 34 36

Sample Output 2

110

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