CF-478C

You have r red, g green and b blue balloons. To decorate a single table for the banquet you need exactly three balloons. Three balloons attached to some table shouldn't have the same color. What maximum number t of tables can be decorated if we know number of balloons of each color?

Your task is to write a program that for given values r, g and b will find the maximum number t of tables, that can be decorated in the required manner.

Input

The single line contains three integers r, g and b (0 ≤ r, g, b ≤ 2·109) — the number of red, green and blue baloons respectively. The numbers are separated by exactly one space.

Output

Print a single integer t — the maximum number of tables that can be decorated in the required manner.

Sample test(s)

input

5 4 3

output

4

input

1 1 1

output

1

input

2 3 3

output

2

Note

In the first sample you can decorate the tables with the following balloon sets: "rgg", "gbb", "brr", "rrg", where "r", "g" and "b" represent the red, green and blue balls, respectively.

 

分析：

1.首先排序，

2.如果前两者之和的两倍小于第三者。那么个数就是前两者之和的个数

3.如果前两者之和的两倍大于第三者。我们可以这么想，先用第三者与前两者2:1平衡掉，然后前两者2:1一直走。也就是总数除以三

#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;
int main()
{
    long long a[3];
    scanf("%lld%lld%lld",&a[0],&a[1],&a[2]);
    sort(a,a+3);
    if((a[0]+a[1])*2<=a[2])
    {
        printf("%d\n",a[0]+a[1]);
    }
    else
    {
        printf("%d\n",(a[0]+a[1]+a[2])/3);
    }
}