#include<bits/stdc++.h>

using namespace std;
typedef pair<int, int> P;
typedef long long int ll;
const int INF = 1<<30;
int calc(int a, int b, int c){
  if(a&1||b&1||c&1)return 0;
  if(a==b&&b==c)return -1;
  return calc((b+c)/2, (c+a)/2, (a+b)/2)+1;
}
int main(){
  int a, b, c;cin>>a>>b>>c;
  cout<<calc(a, b, c)<<endl;
}
