Hacker Zhorik wants to decipher two secret messages he intercepted yesterday. Yeah message is a sequence of encrypted blocks, each of them consists of several bytes of information.

Zhorik knows that each of the messages is an archive containing one or more files. Zhorik knows how each of these archives was transferred through the network: if an archive consists of k files of sizes l1, l2, ..., lk bytes, then the i-th file is split to one or more blocks bi, 1, bi, 2, ..., bi, mi (here the total length of the blocks bi, 1 + bi, 2 + ... + bi, mi is equal to the length of the file li), and after that all blocks are transferred through the network, maintaining the order of files in the archive.

Zhorik thinks that the two messages contain the same archive, because their total lengths are equal. However, each file can be split in blocks in different ways in the two messages.

You are given the lengths of blocks in each of the two messages. Help Zhorik to determine what is the maximum number of files could be in the archive, if the Zhorik's assumption is correct.

Input

The first line contains two integers n, m (1 ≤ n, m ≤ 105) — the number of blocks in the first and in the second messages.

The second line contains n integers x1, x2, ..., xn (1 ≤ xi ≤ 106) — the length of the blocks that form the first message.

The third line contains m integers y1, y2, ..., ym (1 ≤ yi ≤ 106) — the length of the blocks that form the second message.

It is guaranteed that x1 + ... + xn = y1 + ... + ym. Also, it is guaranteed that x1 + ... + xn ≤ 106.

Output

Print the maximum number of files the intercepted array could consist of.

Examples

Input

7 6
2 5 3 1 11 4 4
7 8 2 4 1 8


Output

3


Input

3 3
1 10 100
1 100 10


Output

2


Input

1 4
4
1 1 1 1


Output

1

Note

In the first example the maximum number of files in the archive is 3. For example, it is possible that in the archive are three files of sizes 2 + 5 = 7, 15 = 3 + 1 + 11 = 8 + 2 + 4 + 1 and 4 + 4 = 8.

In the second example it is possible that the archive contains two files of sizes 1 and 110 = 10 + 100 = 100 + 10. Note that the order of files is kept while transferring archives through the network, so we can't say that there are three files of sizes 1, 10 and 100.

In the third example the only possibility is that the archive contains a single file of size 4.
//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.util.*;
import java.math.*;
import java.io.*;
public class R469B {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();
        int x[] = new int[n];
        int y[] = new int[m];
        int ans=0;
        for(int i=0;i<n;i++){
            x[i] = sc.nextInt();
        }
        for(int i=0;i<m;i++){
            y[i] = sc.nextInt();
        }
        int nopx=0,nopy=0, sumx=0, sumy=0;

        while(nopx!=n || nopy!=m){
            if(sumx==0 && sumy==0){
                sumx=x[nopx++];
                sumy = y[nopy++];
            }
            if(sumx<sumy){
                sumx+=x[nopx++];
            }
            if(sumx>sumy){
                sumy+=y[nopy++];
            }
            if(sumx!=0 && sumy!=0 && sumx==sumy){
                ans++;

                sumx=0;
                sumy=0;
            }
           

        }
        System.out.println(ans);


    }

    public static int getCOunt(int[] list1,int[] list2,int n,int m){
        int counter =0;

        int i=0;
        int j =0;
        long sum1 =0,sum2=0;

        while (i!=n || j!=m){


            if(sum1==0 && sum2==0){

                    sum1 = list1[(i++)];


                    sum2 = list2[(j++)];


            }

            if(sum1<sum2){

                    sum1 += list1[(i++)];

            }
            if(sum2<sum1){

                    sum1 += list2[(j++)];

            }

            if(  sum1!=0 && sum2!=0 && sum1== sum2){
                counter++;
                sum1 =0;
                sum2 = 0;
            }
        }

        return counter;


    }
     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;
             }
         }
      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);
                  }
              }
          }

}
