#include <cstdio>
#include <algorithm>

using namespace std;

int main(void) {
  int r, g, b;
  scanf("%d%d%d", &r, &g, &b);
  int a[3] = {r, g, b};
  sort(a, a+3);
  int res = a[0];
  a[1] -= a[0];
  a[2] -= a[0];
  int lb, rb;
  lb = 0; rb = a[2]+1;
  while (rb-lb > 1) {
    int mb = (lb+rb)/2;
    int c = 0;
    int ma = max(a[2]-mb, 0)/2;
    c += ma;
    if (a[1] < mb) {
      c -= mb-a[1];
    } else {
      int mi = max(a[1]-mb, 0)/2;
      c += mi;
    }
    // printf("%d %d %d %d\n", lb, mb, rb, c);
    if (c < mb) rb = mb;
    else lb = mb;
  }
  res += lb;
  printf("%d\n", res);
  return 0;
}