import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int k = sc.nextInt();

		int max = Math.max(Math.max(a, b), c);
		int sum = a + b + c - max;

		for (int i = 0; i < k; i++) {
			max *= 2;
		}

		System.out.println(sum + max);

		sc.close();

	}

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

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int k = sc.nextInt();

		int max = Math.max(Math.max(a, b), c);
		int sum = a + b + c - max;

		for (int i = 0; i < k; i++) {
			max *= 2;
		}

		System.out.println(sum + max);

		sc.close();

	}

} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int k = sc.nextInt();

		int max = Math.max(Math.max(a, b), c);
		int sum = a + b + c - max;

		for (int i = 0; i < k; i++) {
			max *= 2;
		}

		System.out.println(sum + max);

		sc.close();

	} main {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int k = sc.nextInt();

		int max = Math.max(Math.max(a, b), c);
		int sum = a + b + c - max;

		for (int i = 0; i < k; i++) {
			max *= 2;
		}

		System.out.println(sum + max);

		sc.close();

	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a = sc.nextInt(); a sc.nextInt() sc.nextInt sc int b = sc.nextInt(); b sc.nextInt() sc.nextInt sc int c = sc.nextInt(); c sc.nextInt() sc.nextInt sc int k = sc.nextInt(); k sc.nextInt() sc.nextInt sc int max = Math.max(Math.max(a, b), c); max Math.max(Math.max(a, b), c) Math.max Math Math.max(a, b) Math.max Math a b c int sum = a + b + c - max; sum a + b + c - max a + b + c a + b + c a b c max for (int i = 0; i < k; i++) {
			max *= 2;
		} int i = 0; int i = 0; i 0 i < k i k i++ i++ i {
			max *= 2;
		} {
			max *= 2;
		} max *= 2 max 2 System.out.println(sum + max) System.out.println System.out System System.out sum + max sum max sc.close() sc.close sc String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int k = sc.nextInt();

		int max = Math.max(Math.max(a, b), c);
		int sum = a + b + c - max;

		for (int i = 0; i < k; i++) {
			max *= 2;
		}

		System.out.println(sum + max);

		sc.close();

	}

} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int k = sc.nextInt();

		int max = Math.max(Math.max(a, b), c);
		int sum = a + b + c - max;

		for (int i = 0; i < k; i++) {
			max *= 2;
		}

		System.out.println(sum + max);

		sc.close();

	}

} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int k = sc.nextInt();

		int max = Math.max(Math.max(a, b), c);
		int sum = a + b + c - max;

		for (int i = 0; i < k; i++) {
			max *= 2;
		}

		System.out.println(sum + max);

		sc.close();

	}

}
