In order to make the "Sea Battle" game more interesting, Boris decided to add a new ship type to it. The ship consists of two rectangles. The first rectangle has a width of w_1 and a height of h_1, while the second rectangle has a width of w_2 and a height of h_2, where w_1 ≥ w_2. In this game, exactly one ship is used, made up of two rectangles. There are no other ships on the field.

The rectangles are placed on field in the following way:

  * the second rectangle is on top the first rectangle; 
  * they are aligned to the left, i.e. their left sides are on the same line; 
  * the rectangles are adjacent to each other without a gap. 



See the pictures in the notes: the first rectangle is colored red, the second rectangle is colored blue.

Formally, let's introduce a coordinate system. Then, the leftmost bottom cell of the first rectangle has coordinates (1, 1), the rightmost top cell of the first rectangle has coordinates (w_1, h_1), the leftmost bottom cell of the second rectangle has coordinates (1, h_1 + 1) and the rightmost top cell of the second rectangle has coordinates (w_2, h_1 + h_2).

After the ship is completely destroyed, all cells neighboring by side or a corner with the ship are marked. Of course, only cells, which don't belong to the ship are marked. On the pictures in the notes such cells are colored green.

Find out how many cells should be marked after the ship is destroyed. The field of the game is infinite in any direction.

Input

Four lines contain integers w_1, h_1, w_2 and h_2 (1 ≤ w_1, h_1, w_2, h_2 ≤ 10^8, w_1 ≥ w_2) — the width of the first rectangle, the height of the first rectangle, the width of the second rectangle and the height of the second rectangle. You can't rotate the rectangles.

Output

Print exactly one integer — the number of cells, which should be marked after the ship is destroyed.

Examples

Input


2 1 2 1


Output


12


Input


2 2 1 2


Output


16

Note

In the first example the field looks as follows (the first rectangle is red, the second rectangle is blue, green shows the marked squares):

<image>

In the second example the field looks as:

<image>

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

 public class snack4 
{ 
    static class Reader 
    { 
        final private int BUFFER_SIZE = 1 << 16; 
        private DataInputStream din; 
        private byte[] buffer; 
        private int bufferPointer, bytesRead; 
  
        public Reader() 
        { 
            din = new DataInputStream(System.in); 
            buffer = new byte[BUFFER_SIZE]; 
            bufferPointer = bytesRead = 0; 
        } 
  
        public Reader(String file_name) throws IOException 
        { 
            din = new DataInputStream(new FileInputStream(file_name)); 
            buffer = new byte[BUFFER_SIZE]; 
            bufferPointer = bytesRead = 0; 
        } 
  
        public String readLine() throws IOException 
        { 
            byte[] buf = new byte[1000000]; // line length 
            int cnt = 0, c; 
            while ((c = read()) != -1) 
            { 
                if (c == '\n') 
                    break; 
                buf[cnt++] = (byte) c; 
            } 
            return new String(buf, 0, cnt); 
        } 
  
        public int nextInt() throws IOException 
        { 
            int ret = 0; 
            byte c = read(); 
            while (c <= ' ') 
                c = read(); 
            boolean neg = (c == '-'); 
            if (neg) 
                c = read(); 
            do
            { 
                ret = ret * 10 + c - '0'; 
            }  while ((c = read()) >= '0' && c <= '9'); 
  
            if (neg) 
                return -ret; 
            return ret; 
        } 
  
        public long nextLong() throws IOException 
        { 
            long ret = 0; 
            byte c = read(); 
            while (c <= ' ') 
                c = read(); 
            boolean neg = (c == '-'); 
            if (neg) 
                c = read(); 
            do { 
                ret = ret * 10 + c - '0'; 
            } 
            while ((c = read()) >= '0' && c <= '9'); 
            if (neg) 
                return -ret; 
            return ret; 
        } 
  
        public double nextDouble() throws IOException 
        { 
            double ret = 0, div = 1; 
            byte c = read(); 
            while (c <= ' ') 
                c = read(); 
            boolean neg = (c == '-'); 
            if (neg) 
                c = read(); 
  
            do { 
                ret = ret * 10 + c - '0'; 
            } 
            while ((c = read()) >= '0' && c <= '9'); 
  
            if (c == '.') 
            { 
                while ((c = read()) >= '0' && c <= '9') 
                { 
                    ret += (c - '0') / (div *= 10); 
                } 
            } 
  
            if (neg) 
                return -ret; 
            return ret; 
        } 
  
        private void fillBuffer() throws IOException 
        { 
            bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE); 
            if (bytesRead == -1) 
                buffer[0] = -1; 
        } 
  
        private byte read() throws IOException 
        { 
            if (bufferPointer == bytesRead) 
                fillBuffer(); 
            return buffer[bufferPointer++]; 
        } 
  
        public void close() throws IOException 
        { 
            if (din == null) 
                return; 
            din.close(); 
        } 
    } 
 static void merge(int arr[], int l, int m, int r) 
    { 
        // Find sizes of two subarrays to be merged 
        int n1 = m - l + 1; 
        int n2 = r - m; 
  
        /* Create temp arrays */
        int L[] = new int [n1]; 
        int R[] = new int [n2]; 
  
        /*Copy data to temp arrays*/
        for (int i=0; i<n1; ++i) 
            L[i] = arr[l + i]; 
        for (int j=0; j<n2; ++j) 
            R[j] = arr[m + 1+ j]; 
  
  
        /* Merge the temp arrays */
  
        // Initial indexes of first and second subarrays 
        int i = 0, j = 0; 
  
        // Initial index of merged subarry array 
        int k = l; 
        while (i < n1 && j < n2) 
        { 
            if (L[i] <= R[j]) 
            { 
                arr[k] = L[i]; 
                i++; 
            } 
            else
            { 
                arr[k] = R[j]; 
                j++; 
            } 
            k++; 
        } 
  
        /* Copy remaining elements of L[] if any */
        while (i < n1) 
        { 
            arr[k] = L[i]; 
            i++; 
            k++; 
        } 
  
        /* Copy remaining elements of R[] if any */
        while (j < n2) 
        { 
            arr[k] = R[j]; 
            j++; 
            k++; 
        } 
    } 
  
    // Main function that sorts arr[l..r] using 
    // merge() 
    static void sort(int arr[], int l, int r) 
    { 
        if (l < r) 
        { 
            // Find the middle point 
            int m = (l+r)/2; 
  
            // Sort first and second halves 
            sort(arr, l, m); 
            sort(arr , m+1, r); 
  
            // Merge the sorted halves 
            merge(arr, l, m, r); 
        } 
    }
    public static void main(String[] args) throws IOException 
    { 
     //   Reader s=new Reader(); 
        Scanner s=new Scanner(System.in);
        
        long w1=s.nextLong();
        long h1=s.nextLong();
        long w2=s.nextLong();
        long h2=s.nextLong();
        long ans=0;
       
        ans=(w1-w2)+6+2*h1+w1+2*(h2-1)+w2;
        System.out.println(ans);
    }
    
    
    static boolean isPrime(int n) 
    { 
    // Corner cases 
    if (n <= 1) 
        return false; 
    if (n <= 3) 
        return true; 
  
    // This is checked so  
    // that we can skip 
    // middle five numbers 
    // in below loop 
    if (n % 2 == 0 ||  
        n % 3 == 0) 
        return false; 
  
    for (int i = 5; 
             i * i <= n; i = i + 6) 
        if (n % i == 0 || 
            n % (i + 2) == 0) 
            return false; 
  
    return true; 
} 
    static int gcd(int a, int b) 
    { 
      if (b == 0) 
        return a; 
      return gcd(b, a % b);  
    }  
    //void answer(int a,)
    // public static void sortbykey() 
    // { 
    //     // TreeMap to store values of HashMap 
    //     TreeMap<Integer, Integer> sorted = new TreeMap<>(); 
  
    //     // Copy all data from hashMap into TreeMap 
    //     sorted.putAll(count); 
  
    //     // Display the TreeMap which is naturally sorted 
    //     // for (Map.Entry<String, Integer> entry : sorted.entrySet())  
    //     //     // System.out.println("Key = " + entry.getKey() +  
    //     //                  ", Value = " + entry.getValue());         
    // } 
    static long fast_pow(long base,long n,long M)
    {
        if(n==0)
           return 1;
        if(n==1)
        return base;
        long halfn=fast_pow(base,n/2,M);
        if(n%2==0)
            return ( halfn * halfn ) % M;
        else
            return ( ( ( halfn * halfn ) % M ) * base ) % M;
    }
    static long findMMI_fermat(long n,int M)
    {
        return fast_pow(n,M-2,M);
        //gdzjhf
        //zrhzu
    }
} 
