import java.util.*;
import java.io.*;
import java.lang.*;

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

	}
} import java.util.*; util.* java import java.io.*; io.* java import java.lang.*; lang.* java public class Main {
	public static void main (String[] args) {
		Scanner sc = new Scanner(System.in);
		int[] a = new int[3];
		a[0] = sc.nextInt();
		a[1] = sc.nextInt();
		a[2] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort (a);
		int max = a[2];
		for (int i = 0; i<k; i++) {
			max*=2;
		}
		int val = a[0] + a[1] + max;
		System.out.println(val);

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

	} main {
		Scanner sc = new Scanner(System.in);
		int[] a = new int[3];
		a[0] = sc.nextInt();
		a[1] = sc.nextInt();
		a[2] = sc.nextInt();
		int k = sc.nextInt();
		sc.close();
		Arrays.sort (a);
		int max = a[2];
		for (int i = 0; i<k; i++) {
			max*=2;
		}
		int val = a[0] + a[1] + max;
		System.out.println(val);

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

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

	}
} Main
import java.util.*;
import java.io.*;
import java.lang.*;

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

	}
}
