You are at a water bowling training. There are l people who play with their left hand, r people, who play with their right hand, and a ambidexters, who can play with left or right hand.

The coach decided to form a team of even number of players, exactly half of the players should play with their right hand, and exactly half of the players should play with their left hand. One player should use only on of his hands.

Ambidexters play as well with their right hand as with their left hand. In the team, an ambidexter can play with their left hand, or with their right hand.

Please find the maximum possible size of the team, where equal number of players use their left and right hands, respectively.

Input

The only line contains three integers l, r and a (0 ≤ l, r, a ≤ 100) — the number of left-handers, the number of right-handers and the number of ambidexters at the training. 

Output

Print a single even integer — the maximum number of players in the team. It is possible that the team can only have zero number of players.

Examples

Input

1 4 2


Output

6


Input

5 5 5


Output

14


Input

0 2 0


Output

0

Note

In the first example you can form a team of 6 players. You should take the only left-hander and two ambidexters to play with left hand, and three right-handers to play with right hand. The only person left can't be taken into the team.

In the second example you can form a team of 14 people. You have to take all five left-handers, all five right-handers, two ambidexters to play with left hand and two ambidexters to play with right hand.
//package CodeForces;

/*In the name of Allah the Most Merciful.
 * Author
 * Md. Toufiqul Islam
 * Dept. Of CSE
 * Ahsanullah University Of Science And Technology
*/
import java.io.*;
import java.util.*;
import java.math.*;
public class R469A {

    public static void main(String[] args) {
        InputReader sc = new InputReader(System.in);
        OutputWriter out = new OutputWriter(System.out);
        
        int leftHand = sc.nextInt();
        int rightHand = sc.nextInt();
        int ambidexters = sc.nextInt();

        int totalPlayer =0;

        int min = Math.min(leftHand,rightHand);

        totalPlayer += 2*min;

        int remaining =0;

        if(leftHand>min){
            remaining = leftHand-min;
        }
        else if(rightHand>min){
            remaining = rightHand-min;
        }
        

        if(remaining!=0){
            if(remaining<ambidexters){
                totalPlayer += remaining*2;
                ambidexters-=remaining;
            }
            else if(ambidexters<=remaining){
                totalPlayer +=2*ambidexters;
                ambidexters-=ambidexters;
            }
        }

        if(ambidexters%2==0){
            totalPlayer +=ambidexters;
        }
        else {
            totalPlayer += (ambidexters-1);
        }

        out.println(totalPlayer);
        out.close();
    }

     public static class OutputWriter {
             private final PrintWriter writer;

             public OutputWriter(OutputStream outputStream) {
                 writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
             }

             public OutputWriter(Writer writer) {
                 this.writer = new PrintWriter(writer);
             }

             public void print(char[] array) {
                 writer.print(array);
             }

             public void print(Object... objects) {
                 for (int i = 0; i < objects.length; i++) {
                     if (i != 0) {
                         writer.print(' ');
                     }
                     writer.print(objects[i]);
                 }
             }

             public void print(int[] array) {
                 for (int i = 0; i < array.length; i++) {
                     if (i != 0) {
                         writer.print(' ');
                     }
                     writer.print(array[i]);
                 }
             }

             public void print(double[] array) {
                 for (int i = 0; i < array.length; i++) {
                     if (i != 0) {
                         writer.print(' ');
                     }
                     writer.print(array[i]);
                 }
             }

             public void print(long[] array) {
                 for (int i = 0; i < array.length; i++) {
                     if (i != 0) {
                         writer.print(' ');
                     }
                     writer.print(array[i]);
                 }
             }

             public void println(int[] array) {
                 print(array);
                 writer.println();
             }

             public void println(double[] array) {
                 print(array);
                 writer.println();
             }

             public void println(long[] array) {
                 print(array);
                 writer.println();
             }

             public void println() {
                 writer.println();
             }

             public void println(Object... objects) {
                 print(objects);
                 writer.println();
             }

             public void print(char i) {
                 writer.print(i);
             }

             public void println(char i) {
                 writer.println(i);
             }

             public void println(char[] array) {
                 writer.println(array);
             }

             public void printf(String format, Object... objects) {
                 writer.printf(format, objects);
             }

             public void close() {
                 writer.close();
             }

             public void flush() {
                 writer.flush();
             }

             public void print(long i) {
                 writer.print(i);
             }

             public void println(long i) {
                 writer.println(i);
             }

             public void print(int i) {
                 writer.print(i);
             }

             public void println(int i) {
                 writer.println(i);
             }

             public void separateLines(int[] array) {
                 for (int i : array) {
                     println(i);
                 }
             }
         }
      public static class InputReader {
              private boolean finished = false;

              private InputStream stream;
              private byte[] buf = new byte[1024];
              private int curChar;
              private int numChars;
              private SpaceCharFilter filter;

              public InputReader(InputStream stream) {
                  this.stream = stream;
              }

              public int read() {
                  if (numChars == -1) {
                      throw new InputMismatchException();
                  }
                  if (curChar >= numChars) {
                      curChar = 0;
                      try {
                          numChars = stream.read(buf);
                      } catch (IOException e) {
                          throw new InputMismatchException();
                      }
                      if (numChars <= 0) {
                          return -1;
                      }
                  }
                  return buf[curChar++];
              }

              public int peek() {
                  if (numChars == -1) {
                      return -1;
                  }
                  if (curChar >= numChars) {
                      curChar = 0;
                      try {
                          numChars = stream.read(buf);
                      } catch (IOException e) {
                          return -1;
                      }
                      if (numChars <= 0) {
                          return -1;
                      }
                  }
                  return buf[curChar];
              }

              public int nextInt() {
                  int c = read();
                  while (isSpaceChar(c)) {
                      c = read();
                  }
                  int sgn = 1;
                  if (c == '-') {
                      sgn = -1;
                      c = read();
                  }
                  int res = 0;
                  do {
                      if (c < '0' || c > '9') {
                          throw new InputMismatchException();
                      }
                      res *= 10;
                      res += c - '0';
                      c = read();
                  } while (!isSpaceChar(c));
                  return res * sgn;
              }

              public long nextLong() {
                  int c = read();
                  while (isSpaceChar(c)) {
                      c = read();
                  }
                  int sgn = 1;
                  if (c == '-') {
                      sgn = -1;
                      c = read();
                  }
                  long res = 0;
                  do {
                      if (c < '0' || c > '9') {
                          throw new InputMismatchException();
                      }
                      res *= 10;
                      res += c - '0';
                      c = read();
                  } while (!isSpaceChar(c));
                  return res * sgn;
              }

              public String nextString() {
                  int c = read();
                  while (isSpaceChar(c)) {
                      c = read();
                  }
                  StringBuilder res = new StringBuilder();
                  do {
                      if (Character.isValidCodePoint(c)) {
                          res.appendCodePoint(c);
                      }
                      c = read();
                  } while (!isSpaceChar(c));
                  return res.toString();
              }

              public boolean isSpaceChar(int c) {
                  if (filter != null) {
                      return filter.isSpaceChar(c);
                  }
                  return isWhitespace(c);
              }

              public static boolean isWhitespace(int c) {
                  return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
              }

              private String readLine0() {
                  StringBuilder buf = new StringBuilder();
                  int c = read();
                  while (c != '\n' && c != -1) {
                      if (c != '\r') {
                          buf.appendCodePoint(c);
                      }
                      c = read();
                  }
                  return buf.toString();
              }

              public String readLine() {
                  String s = readLine0();
                  while (s.trim().length() == 0) {
                      s = readLine0();
                  }
                  return s;
              }

              public String readLine(boolean ignoreEmptyLines) {
                  if (ignoreEmptyLines) {
                      return readLine();
                  } else {
                      return readLine0();
                  }
              }

              public BigInteger readBigInteger() {
                  try {
                      return new BigInteger(nextString());
                  } catch (NumberFormatException e) {
                      throw new InputMismatchException();
                  }
              }

              public char nextCharacter() {
                  int c = read();
                  while (isSpaceChar(c)) {
                      c = read();
                  }
                  return (char) c;
              }

              public double nextDouble() {
                  int c = read();
                  while (isSpaceChar(c)) {
                      c = read();
                  }
                  int sgn = 1;
                  if (c == '-') {
                      sgn = -1;
                      c = read();
                  }
                  double res = 0;
                  while (!isSpaceChar(c) && c != '.') {
                      if (c == 'e' || c == 'E') {
                          return res * Math.pow(10, nextInt());
                      }
                      if (c < '0' || c > '9') {
                          throw new InputMismatchException();
                      }
                      res *= 10;
                      res += c - '0';
                      c = read();
                  }
                  if (c == '.') {
                      c = read();
                      double m = 1;
                      while (!isSpaceChar(c)) {
                          if (c == 'e' || c == 'E') {
                              return res * Math.pow(10, nextInt());
                          }
                          if (c < '0' || c > '9') {
                              throw new InputMismatchException();
                          }
                          m /= 10;
                          res += (c - '0') * m;
                          c = read();
                      }
                  }
                  return res * sgn;
              }

              public boolean isExhausted() {
                  int value;
                  while (isSpaceChar(value = peek()) && value != -1) {
                      read();
                  }
                  return value == -1;
              }

              public String next() {
                  return nextString();
              }

              public SpaceCharFilter getFilter() {
                  return filter;
              }

              public void setFilter(SpaceCharFilter filter) {
                  this.filter = filter;
              }

              public interface SpaceCharFilter {
                  public boolean isSpaceChar(int ch);
              }
              public int[] nextIntArray(int n){
                  int[] array=new int[n];
                  for(int i=0;i<n;++i)array[i]=nextInt();
                  return array;
              }
              public int[] nextSortedIntArray(int n){
                  int array[]=nextIntArray(n);
                  Arrays.sort(array);
                  return array;
              }
              public int[] nextSumIntArray(int n){
                  int[] array=new int[n];
                  array[0]=nextInt();
                  for(int i=1;i<n;++i)array[i]=array[i-1]+nextInt();
                  return array;
              }
              public long[] nextLongArray(int n){
                  long[] array=new long[n];
                  for(int i=0;i<n;++i)array[i]=nextLong();
                  return array;
              }
              public long[] nextSumLongArray(int n){
                  long[] array=new long[n];
                  array[0]=nextInt();
                  for(int i=1;i<n;++i)array[i]=array[i-1]+nextInt();
                  return array;
              }
              public long[] nextSortedLongArray(int n){
                  long array[]=nextLongArray(n);
                  Arrays.sort(array);
                  return array;
              }
          }

}
