#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include <iomanip>
using namespace std;

int main(){
    int a, b, c, d, sum1, m;
    cin >> a >> b >> c >> d;
    m = max(c, max(a, b));
    cout << (((a + b + c + d) > m * 3) ? (a + b + c + d) : (m * 3)) << endl;
}