993 992 991
 100 1 10
 960 935 994
 99 8 99
 60 16 1
 759 10 258
 24 19 9
 196 169 144
 1000 999 1
 945 812 917
 1000 100 10
 500 300 300
 888 777 1000
 2 1 4
 24 12 12
 767 2 514
 2 1 2
 1000 1 1
 5 2 1
 70 32 1
 765 123 899
 17 7 10
 5 4 10
 888 777 888
 66 38 4
 1000 999 1000
 9 3 300
 244 87 4
 765 123 45
 1000 1 1000
 305 203 421
 100 10 1
 64 12 8
 894 1 999
 2 1 1
 18 14 10
 6 2 4
 888 777 1
 27 26 1
 2 1 3
 5 1 5
 7 3 200
 561 31 917
 17 10 7
 93 74 831

1
 990
 27
 1127
 3
 19325
 3
 24
 1
 151
 90
 200
 143
 4
 12
 196605
 2
 999
 2
 2
 4693
 15
 3
 127
 3
 2
 600
 8
 235
 999000
 212
 9
 35
 892107
 1
 3
 8
 1
 1
 3
 20
 267
 15678
 5
 214

#include <bits/stdc++.h>
using namespace std;
int d2x[] = {1, -1, 0, 0, 1, -1, 1, -1};
int d2y[] = {0, 0, 1, -1, 1, -1, -1, 1};
int d3x[] = {1, -1, 0, 0, 0, 0};
int d3y[] = {0, 0, 1, -1, 0, 0};
int d3z[] = {0, 0, 0, 0, 1, -1};
struct edge {
  int from, to, w;
  edge(int from, int to, int w) : from(from), to(to), w(w) {}
  bool operator<(const edge& e) const { return w > e.w; }
};
const double EPS = (1e-9);
int a, v, c, data;
bool p(int val);
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  ;
  cin >> a >> v >> c;
  data = a * c;
  int low = 0, high = 1000, mid;
  while (low < high) {
    mid = (low + high) / 2;
    if (p(mid)) {
      high = mid;
    } else {
      low = mid + 1;
    }
  }
  cout << low << endl;
  return 0;
}
bool p(int val) {
  int t = (data - val * v) / v + ((data - val * v) % v != 0);
  return (val * v + v * t >= data && val * v + v * t >= a * t);
}
