#include <bits/stdc++.h>
using namespace std;
int n, x, y;
void solve() {
  int ted = y * n;
  if (ted % 100)
    ted = ted / 10 + 1;
  else
    ted /= 10;
  if (ted > x)
    cout << ted - x << endl;
  else
    cout << "0" << endl;
}
int main() {
  cin >> n >> x >> y;
  solve();
  return 0;
}
