9 530792195 6
 0 0 10
 1944219055 454183506 1369298327
 914835 2742837 9234739
 10 10 0
 2 2 0
 0 0 1
 3 10 1007169359
 0 1 0
 1016450951 2 9
 0 2 10
 2147483648 0 2147483647
 92134834 23742837 92374738
 1 4 3
 382601556 881329640 791556039
 0 0 58
 5 10 6
 10 6 8
 6 8 10
 3 2 0
 1 4 4
 2147483630 2147483642 2147483610
 1 0 0
 18 67 5
 50606342 2 1134945035
 8 97 83
 2147483648 0 0
 92134834 23742837 92374737
 5 0 5
 772486757 1747374885 377299255
 1 0 1
 1 2 3
 0 3 2
 2147483648 2147483647 2147483648
 51 10 91
 9214834 2742837 9234739
 1 2 2147483648
 67 81 1
 92134834 23742837 92374739
 2 7 95
 3 0 2
 5 9 0
 1 10 2
 246543403 71853598 1504509195
 2147483648 2147483648 2147483648
 48 6 7
 2147483648 2147483648 0
 1358352906 27037371 1947040615

                                                       530792195
                                                                0
                                                       1944219055
                                                          2742837
                                                               10
                                                                2
                                                                0
                                                       1007169359
                                                                0
                                                       1016450951
                                                                2
 2147483648                                                         92374738
                                                                3
                                                        881329640
                                                                0
                                                               10
                                                                8
                                                                8
                                                                2
                                                                4
                                                       2147483630
                                                                0
                                                               67
                                                         50606342
                                                               97
                                                                0
                                                         92374737
                                                                5
                                                        772486757
                                                                1
                                                                3
                                                                2
 2147483648                                                               91
                                                          9234739
 2147483648                                                               67
                                                         92374739
                                                               95
                                                                2
                                                                9
                                                               10
                                                       1504509195
 2147483648                                                               48
 2147483648                                                       1947040615

#include <bits/stdc++.h>
using namespace std;
const int mod = 1000000000 + 7;
int bs(int *st, int *en, int val, char c) {
  int k;
  if (c == 'l') k = lower_bound(st, en, val) - st;
  if (c == 'u') k = upper_bound(st, en, val) - st;
  return k;
}
int prime[780500];
int sieve() {
  int a, b, c;
  c = 0;
  prime[c] = 2;
  bool *m = (bool *)calloc(1000006, sizeof(bool));
  for (a = 3; a <= 1000000; a = a + 2) {
    if (!m[a]) {
      prime[++c] = a;
      for (b = 2 * a; b <= 1000000; b = b + a) m[b] = true;
    }
  }
  free(m);
  return c;
}
vector<long long> primes;
const int N = 15000000;
int lp[N + 1];
void genPrimes() {
  primes.reserve(N / 10);
  for (int i = 2; i <= N; ++i) {
    if (lp[i] == 0) {
      lp[i] = i;
      primes.push_back(i);
    }
    for (int j = 0; j < primes.size(); j++) {
      int p = primes[j];
      int q = i * p;
      if (q > N || p > lp[i]) {
        break;
      }
      lp[q] = p;
    }
  }
}
long long bigmod(long long a, long long n) {
  n %= mod - 1;
  long long res = 1;
  while (n) {
    if (n & 1ll) {
      res = res * a;
      if (res >= mod) {
        res %= mod;
      }
    }
    a = a * a;
    if (a >= mod) {
      a %= mod;
    }
    n >>= 1;
  }
  return res;
}
int main() {
  long long a, b, c, d, e, x, y, z;
  long long A, B, C;
  cin >> A >> B >> C;
  x = 0;
  if (!A) x++;
  if (!B) x++;
  if (!C) x++;
  if (x >= 2) {
    printf("0\n");
    return 0;
  }
  x = 0;
  if (A == B) x++;
  if (B == C) x++;
  if (C == A) x++;
  if (x >= 1) {
    printf("1\n");
    return 0;
  }
  z = 0;
  vector<long long> v;
  v.clear();
  v.push_back(A);
  v.push_back(B);
  v.push_back(C);
  sort(v.begin(), v.end());
  C = v[0];
  B = v[1];
  A = v[2];
  if (C) z = z + C;
  y = B - C;
  A = A + C;
  x = A / (B - C);
  z = z + x * y;
  z = z + (A % (B - C));
  cout << z << endl;
  return 0;
}
