// yukicoder: No.91 赤、緑、青の石
// 2019.6.22 bal4u

#include <stdio.h>
#include <stdlib.h>

int cmp(const void *a, const void *b) { return *(int *)b - *(int *)a; }

int bsch(int A, int B)
{
	int a, b, l = 0, r = B;

    while (l+1 < r) {
        b = (l + r) >> 1;
		a = (B - b) / 3;
		if (a + 3*b > A) r = b;
		else l = b;
    }
	return l
	;
}

int main()
{
	int i, A[3], ans;

	for (i = 0; i < 3; i++) scanf("%d", A+i);
	qsort(A, 3, sizeof(int), cmp);
	ans = A[2], A[0] -= ans, A[1] -= ans;
	
	if (A[1] > 0) {
		if (A[0] >= 3*A[1]) ans += A[1], A[0] -= A[1]*3, A[1] = 0;
		else if (A[0] >= 3) {
			int a, b;
			b = bsch(A[0], A[1]);
			a = (A[1] - b)/3;
			ans += a + b;
			A[0] -= a + 3*b, A[1] -= 3*a + b;
		}
	}

	ans += A[0]/5;
	printf("%d\n", ans);
	return 0;
}