16953번

16953

#include <iostream>
#include <algorithm>

using namespace std;

long long min_result = 987654321;

void getAnswer(long long a, long long b, long long cnt) {
    if(a==b) {
        min_result = min(min_result, cnt);
        return;
    }
    else {
        if(a<b) {
            getAnswer(a*2, b, cnt+1);
            getAnswer(a*10+1, b, cnt+1);
        }
    }
}

int main() {
    long long a,b;
    cin>>a>>b;
    getAnswer(a,b,0);

    if(min_result==987654321) {
        cout<<-1;
    } else {
        cout<<min_result+1;
    }
}