import std.algorithm;
import std.array;
import std.ascii;
import std.bigint;
import std.complex;
import std.container;
import std.conv;
import std.functional;
import std.math;
import std.range;
import std.stdio;
import std.string;
import std.typecons;

auto readInts() {
	return array(map!(to!int)(readln().strip().split()));
}
auto readInt() {
	return readInts()[0];
}
auto readLongs() {
	return array(map!(to!long)(readln().strip().split()));
}
auto readLong() {
	return readLongs()[0];
}

void readlnTo(T...)(ref T t) {
    auto s = readln().split();
    assert(s.length == t.length);
    foreach(ref ti; t) {
        ti = s[0].to!(typeof(ti));
        s = s[1..$];
    }
}

const real eps = 1e-10;

const long p = 1_000_000_000 + 7;

void main(){
    long a, b, c;
    readlnTo(a, b, c);
    auto x = [a, b, c];
    x.sort();

    bool[long[]] used;
    long ans;
    while(x.all!(a => a % 2 == 0)) {
        if((x in used) !is null) {
            ans = -1;
            break;
        }
        ++ans;
        used[x.idup] = true;
        x = [(x[0]+x[1])/2, (x[1]+x[2])/2, (x[2]+x[0])/2];
        x.sort();
    }
    writeln(ans);
}

