#include <bits/stdc++.h>

#define rep(i, n) for (int (i) = 0; (i) < (int)(n); (i)++)

const int dx[] = {1, 0, -1, 0};
const int dy[] = {0, 1, 0, -1};
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef pair<int, int> pii;

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    int x, y, x2, y2;
    cin >> x >> y;
    cin >> x2 >> y2;
    if (x != y || x2 != y2) {
        cout << max(x, y) << endl;
    } else {
        if (x2 < x) {
            cout << x+1 << endl;
        } else {
            cout << x << endl;
        }
    }
    return 0;
}