Ciel and Flowers

题意翻译

Fox Ciel有r朵红花，g朵绿花和b朵蓝花。她想用这些花做几个花束。 有四种类型的花束： - 制作“红色花束”，要3朵红花 - 制作“绿色花束”，要3朵绿花 - 制作“蓝色花束”，要3朵蓝花 - 制作“混合花束”，要1朵红，1朵绿和1朵蓝花 输出可以制作的最大数量的花束。

题目描述

Fox Ciel has some flowers: $ r $ red flowers, $ g $ green flowers and $ b $ blue flowers. She wants to use these flowers to make several bouquets. There are 4 types of bouquets: - To make a "red bouquet", it needs 3 red flowers. - To make a "green bouquet", it needs 3 green flowers. - To make a "blue bouquet", it needs 3 blue flowers. - To make a "mixing bouquet", it needs 1 red, 1 green and 1 blue flower. Help Fox Ciel to find the maximal number of bouquets she can make.

输入输出格式

输入格式

The first line contains three integers $ r $ , $ g $ and $ b $ ( $ 0<=r,g,b<=10^{9} $ ) — the number of red, green and blue flowers.

输出格式

Print the maximal number of bouquets Fox Ciel can make.

输入输出样例

输入样例 #1

3 6 9

输出样例 #1

6

输入样例 #2

4 4 4

输出样例 #2

4

输入样例 #3

0 0 0

输出样例 #3

0

说明

In test case 1, we can make 1 red bouquet, 2 green bouquets and 3 blue bouquets. In test case 2, we can make 1 red, 1 green, 1 blue and 1 mixing bouquet.