You are given n numbers a_1, a_2, ..., a_n. With a cost of one coin you can perform the following operation:

Choose one of these numbers and add or subtract 1 from it.

In particular, we can apply this operation to the same number several times.

We want to make the product of all these numbers equal to 1, in other words, we want a_1 ⋅ a_2 ... ⋅ a_n = 1. 

For example, for n = 3 and numbers [1, -3, 0] we can make product equal to 1 in 3 coins: add 1 to second element, add 1 to second element again, subtract 1 from third element, so that array becomes [1, -1, -1]. And 1⋅ (-1) ⋅ (-1) = 1.

What is the minimum cost we will have to pay to do that?

Input

The first line contains a single integer n (1 ≤ n ≤ 10^5) — the number of numbers.

The second line contains n integers a_1, a_2, ..., a_n (-10^9 ≤ a_i ≤ 10^9) — the numbers.

Output

Output a single number — the minimal number of coins you need to pay to make the product equal to 1.

Examples

Input


2
-1 1


Output


2

Input


4
0 0 0 0


Output


4

Input


5
-5 -3 5 3 0


Output


13

Note

In the first example, you can change 1 to -1 or -1 to 1 in 2 coins.

In the second example, you have to apply at least 4 operations for the product not to be 0.

In the third example, you can change -5 to -1 in 4 coins, -3 to -1 in 2 coins, 5 to 1 in 4 coins, 3 to 1 in 2 coins, 0 to 1 in 1 coin.

import java.io.OutputStream;
import java.util.*;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.io.BufferedWriter;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.util.NoSuchElementException;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Egor Kulikov (egor@egork.net)
 */


public class Main {

    public static void main(String[] args) {

        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        OutputWriter out = new OutputWriter(outputStream);
        Solution solver = new Solution();
		//   int testCount = Integer.parseInt(in.next());

		//    for (int i = 1; i <= testCount; i++) {
		solver.solve(0, in, out);

        //}
        out.close();
    }
//**********************SOLVE    HERE     EVERYTHING******************************



    //1 2 3 4 5 
    static class Solution
    {

        public void solve(int testNumber, InputReader in, OutputWriter out)
        {
            int n=in.readInt(); long sum=0;
            long arr[]=new long[n],arr2[]=new long[n];
            for(int i=0;i<n;i++)
            {
                arr[i]=Long.parseLong(in.readString());
                if(arr[i]<-1)
                {
                    sum+=Math.abs(arr[i])-1;
                    arr2[i]=-1;
                }
                else if(arr[i]>1)
                {
                    sum+=arr[i]-1;
                    arr2[i]=1;
                }
                else if(arr[i]==0)
                {
                    sum+=1;
                    arr2[i]=1;
                }
				else {
					arr2[i]=arr[i];
				}
            }
            int pro=1,c=0;
            for(int i=0;i<n;i++)
            {
                pro*=arr2[i];
                if(arr[i]==0)
                    c++;
            }
            if(pro==1)
            {
                System.out.println(sum);return;
            }
            else
            {
                if(c>0)
                {
                    System.out.println(sum);return;
                }
                else
                {
                    sum+=2;
                    System.out.println(sum);
                    return;
                }

            }


        }
    }

//*********************END        HERE       EVERYTHING*******************************    

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private InputReader.SpaceCharFilter filter;

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

        public void readIntArrays(int[]... arrays) {
            for (int i = 0; i < arrays[0].length; i++) {
                for (int j = 0; j < arrays.length; j++) {
                    arrays[j][i] = readInt();
                }
            }
        }

        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 readInt() {
            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 String readString() {
            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;
        }

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

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);

        }

    }

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

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

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

    }


}


