#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c, i, res;
  while (~scanf("%d%d%d", &a, &b, &c)) {
    res = 0;
    for (i = 0; i < 3; i++) {
      if (min(a, min(b, c)) >= i)
        res = max(res, ((a - i) / 3 + (b - i) / 3 + (c - i) / 3) + i);
    }
    printf("%d\n", res);
  }
}
