#include <bits/stdc++.h>
using namespace std;
const int inf = 0x3f3f3f3f;
const int maxn = 1e5 + 5;
int r, b, g;
int main() {
  while (~scanf("%d%d%d", &r, &g, &b)) {
    int ans = 0;
    int Min = min(r, min(g, b));
    if (Min >= 2) {
      int t1 = r / 3 + g / 3 + b / 3;
      int t2 = 1 + (r - 1) / 3 + (g - 1) / 3 + (b - 1) / 3;
      int t3 = 2 + (r - 2) / 3 + (g - 2) / 3 + (b - 2) / 3;
      ans = max(t1, max(t2, t3));
    } else if (Min == 1) {
      int t1 = r / 3 + g / 3 + b / 3;
      int t2 = 1 + (r - 1) / 3 + (g - 1) / 3 + (b - 1) / 3;
      ans = max(t1, t2);
    } else {
      ans = r / 3 + g / 3 + b / 3;
    }
    printf("%d\n", ans);
  }
  return 0;
}
