#include <bits/stdc++.h>
using namespace std;

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

bool ok(const string& a, const string& b) {
    rep(i,0,sz(a)) {
        if (a[i] - '0' + b[i] - '0' > 9) return false;
    }
    return true;
}

void neg(string& x) {
    x[0]--;
    rep(i,0,sz(x)) {
        if (x[i] < '0') {
            x[i] = '9';
            x[i+1]--;
        }
    }
}

void add(string& x) {
    x[0]++;
    rep(i,0,sz(x)) {
        if (x[i] > '9') {
            x[i] = '0';
            x[i+1]++;
        }
    }
}

string solve(string a, string b) {
    string res(sz(a), '0');
    while (!ok(a, b)) {
        neg(a);
        add(b);
        add(res);
    }
    return res;
}

int main() {
	cin.tie(0)->sync_with_stdio(0);
	cin.exceptions(cin.failbit);

    string a, b;
    cin >> a >> b;

    reverse(all(a));
    reverse(all(b));
    while (sz(a) < sz(b)) a.push_back('0');
    while (sz(a) > sz(b)) b.push_back('0');

    // In case of carry.
    a.push_back('0');
    b.push_back('0');

    string r1 = solve(a, b);
    string r2 = solve(b, a);
    reverse(all(r1));
    reverse(all(r2));
    string res = min(r1, r2);

    reverse(all(res));
    while (sz(res) > 1 && res.back() == '0') res.pop_back();
    reverse(all(res));

    cout << res << endl;
}