#include <iostream>
#include <algorithm>
using namespace std;

int main(void)
{
	int a[3], riz = 0;
	scanf("%d", &a[0]);
	scanf("%d", &a[1]);
	scanf("%d", &a[2]);
	
	sort(a, a + 3);

	riz += a[0];

	a[1] -= a[0];
	a[2] -= a[0];


	if((a[2] - a[1]) / 2 >= a[1])
	{
		riz += a[1];
		a[2] -= a[1] * 3;
		riz += a[2] / 5;
	}
	else
	{
		int tmp = (a[2] - a[1]) / 2;
		riz += tmp;
		a[1] -= tmp;
		a[2] -= tmp * 3;

		riz += (a[1] / 4) * 2;
		a[2] %= 4;

		if(a[2] >= 3)
			riz++;
	}

	printf("%d\n", riz);

	return 0;
}