void main() {
	enum INF = 10 ^^ 7;
	enum M = 30;
	const N = 4;
	auto V = new int[N];
	foreach (i; 0 .. N) {
		V[i] = readInt;
	}
	int ans = INF;
	foreach (i; 1 .. M + 1) {
		foreach (j; i + 1 .. M + 1) {
			foreach (k; j + 1 .. M + 1) {
				int now;
				foreach (l; 0 .. N) {
					auto dp = new int[V[l] + 1];
					dp[] = INF;
					dp[0] = 0;
					foreach (m; 0 .. V[l]) {
						foreach (n; [i, j, k]) {
							if (m + n > V[l]) continue;
							chmin(dp[m + n], dp[m] + 1);
						}
					}
					now += dp[V[l]];
				}
				chmin(ans, now);
			}
		}
	}
	ans.writeln;
}

import std,core.bitop;
string[]_R;
string readString(){while(_R.empty){_R=readln.chomp.split;}auto ret=_R.front;_R.popFront;return ret;}
int readInt(){return readString.to!int;}
long readLong(){return readString.to!long;}
ulong readULong(){return readString.to!ulong;}
real readReal(){return readString.to!real;}
bool chmin(T)(ref T A,T B){if(A>B){A=B;return true;}else{return false;}}
bool chmax(T)(ref T A,T B){if(A<B){A=B;return true;}else{return false;}}
int lowerBound(T)(T[]A,T x){int L=-1,R=cast(int)A.length;while(R-L>1){int mid=(L+R)/2;(A[mid]<x?L:R)=mid;}return R;}
int upperBound(T)(T[]A,T x){int L=-1,R=cast(int)A.length;while(R-L>1){int mid=(L+R)/2;(A[mid]<=x?L:R)=mid;}return R;}