import java.util.*;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a[] = new int[3];
		for(int i = 0; i < 3; ++i)
			a[i] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort(a);
		int tmp = (int)Math.pow(2,  k);
		int ans = a[0] + a[1] + a[2] * tmp;
		System.out.println(ans);
	}

} import java.util.*; util.* java public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a[] = new int[3];
		for(int i = 0; i < 3; ++i)
			a[i] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort(a);
		int tmp = (int)Math.pow(2,  k);
		int ans = a[0] + a[1] + a[2] * tmp;
		System.out.println(ans);
	}

} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a[] = new int[3];
		for(int i = 0; i < 3; ++i)
			a[i] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort(a);
		int tmp = (int)Math.pow(2,  k);
		int ans = a[0] + a[1] + a[2] * tmp;
		System.out.println(ans);
	} main {
		Scanner sc = new Scanner(System.in);
		int a[] = new int[3];
		for(int i = 0; i < 3; ++i)
			a[i] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort(a);
		int tmp = (int)Math.pow(2,  k);
		int ans = a[0] + a[1] + a[2] * tmp;
		System.out.println(ans);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a[] = new int[3]; a new int[3] 3 for(int i = 0; i < 3; ++i)
			a[i] = sc.nextInt(); int i = 0; int i = 0; i 0 i < 3 i 3 ++i ++i i a[i] = sc.nextInt(); a[i] = sc.nextInt() a[i] a i sc.nextInt() sc.nextInt sc int k = sc.nextInt(); k sc.nextInt() sc.nextInt sc sc.close() sc.close sc Arrays.sort(a) Arrays.sort Arrays a int tmp = (int)Math.pow(2,  k); tmp (int)Math.pow(2,  k) Math.pow Math 2 k int ans = a[0] + a[1] + a[2] * tmp; ans a[0] + a[1] + a[2] * tmp a[0] + a[1] + a[2] * tmp a[0] a 0 a[1] a 1 a[2] * tmp a[2] a 2 tmp System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a[] = new int[3];
		for(int i = 0; i < 3; ++i)
			a[i] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort(a);
		int tmp = (int)Math.pow(2,  k);
		int ans = a[0] + a[1] + a[2] * tmp;
		System.out.println(ans);
	}

} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a[] = new int[3];
		for(int i = 0; i < 3; ++i)
			a[i] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort(a);
		int tmp = (int)Math.pow(2,  k);
		int ans = a[0] + a[1] + a[2] * tmp;
		System.out.println(ans);
	}

} Main
import java.util.*;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a[] = new int[3];
		for(int i = 0; i < 3; ++i)
			a[i] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort(a);
		int tmp = (int)Math.pow(2,  k);
		int ans = a[0] + a[1] + a[2] * tmp;
		System.out.println(ans);
	}

}
