int funcc(int a, int b, int c, int d) { int max_of_four = a;

if (b > max_of_four) {
    max_of_four = b;
}
if (c > max_of_four) {
    max_of_four = c;
}
if (d > max_of_four) {
    max_of_four = d;
}

return max_of_four;

}

int main() { int a, b, c, d; cin >> a >> b >> c >> d;

int max_value = funcc(a, b, c, d);
cout << max_value << endl;

return 0;

}