You are given a bracket sequence s consisting of n opening '(' and closing ')' brackets.

A regular bracket sequence is a bracket sequence that can be transformed into a correct arithmetic expression by inserting characters '1' and '+' between the original characters of the sequence. For example, bracket sequences "()()", "(())" are regular (the resulting expressions are: "(1)+(1)", "((1+1)+1)"), and ")(" and "(" are not.

You can change the type of some bracket s_i. It means that if s_i =  ')' then you can change it to '(' and vice versa.

Your task is to calculate the number of positions i such that if you change the type of the i-th bracket, then the resulting bracket sequence becomes regular.

Input

The first line of the input contains one integer n (1 ≤ n ≤ 10^6) — the length of the bracket sequence.

The second line of the input contains the string s consisting of n opening '(' and closing ')' brackets.

Output

Print one integer — the number of positions i such that if you change the type of the i-th bracket, then the resulting bracket sequence becomes regular.

Examples

Input


6
(((())


Output


3


Input


6
()()()


Output


0


Input


1
)


Output


0


Input


8
)))(((((


Output


0
import java.io.*;
import java.math.BigInteger;
import java.math.RoundingMode;
import java.text.DecimalFormat;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.net.ssl.SSLContext;

public class Main
{  
   static long mod=(long)(1e+9 + 7);
   static int[] sieve;
   static ArrayList<Integer> primes;

   
   public static void main(String[] args) throws java.lang.Exception
   {	  	
	     fast s = new fast();
	     PrintWriter out=new PrintWriter(System.out);
	     Scanner sc=new Scanner(System.in);
	     StringBuilder fans = new StringBuilder();
	     
	     int n=s.nextInt();
	     
	     String str=s.nextLine();
	     
	     int a[]=new int[n];
	     int b[]=new int[n];
	     int c[]=new int[n];
	     int mini[]=new int[n];
	     int mini1[]=new int[n];
	     
	     for(int i=0;i<n;i++)
	    	 if(str.charAt(i)=='(') {a[i]=1;b[i]=1;c[i]=1;}
	    	 else {a[i]=-1;b[i]=-1;c[i]=-1;}
	     
	     for(int i=1;i<n;i++) a[i]+=a[i-1];
	     for(int i=n-2;i>=0;i--) c[i]+=c[i+1];
	     
	     int min=Integer.MAX_VALUE;
	     for(int i=n-1;i>=0;i--) {min=Math.min(a[i], min);mini[i]=min;}
	     min=Integer.MAX_VALUE;
	     for(int i=0;i<n;i++) {min=Math.min(a[i], min);mini1[i]=min;}
	      
	     if(!(a[n-1]==2 || a[n-1]==-2)) System.out.println("0");
	     else
	    	 {
	    		 int count=0;	    			
	    		 if(a[n-1]==2)
	    			 {
	    				 for(int i=0;i<n;i++) 
	    					 {
	    						 if((a[i]-2)>=0 && b[i]==1) 
	    					       {
	    						     count++;
	    						     if(((i+1)<n && mini[i+1]<2) || ((i-1)>=0 && mini1[i-1]<0)) count--; 
	    						   }
	    					 }
	    				 System.out.println(count);	    					 
	    			 }
	    		 else
	    			 {
	    				 for(int i=0;i<n;i++) 
	    					 {
	    					 if((a[i]+2)>=0 && b[i]==-1) 
	    						 {
	    			                 count++;
	    			                 if(((i+1)<n && mini[i+1]<-2) || ((i-1)>=0 && mini1[i-1]<0) )count--;	
	    						 }
	    					 }	
	    				 System.out.println(count);    				 
	    			 }
	    	 }
   }
  
   
   
static class fast {   

	private InputStream i;
		private byte[] buf = new byte[1024];
		private int curChar;
		private int numChars;
		
		//Return floor log2n
		public static int log2(int bits) // returns 0 for bits=0
			{
			    int log = 0;
			    if( ( bits & 0xffff0000 ) != 0 ) { bits >>>= 16; log = 16; }
			    if( bits >= 256 ) { bits >>>= 8; log += 8; }
			    if( bits >= 16  ) { bits >>>= 4; log += 4; }
			    if( bits >= 4   ) { bits >>>= 2; log += 2; }
			    return log + ( bits >>> 1 );
			}
		
		public static boolean next_permutation(int a[])
		   {
			   int i=0,j=0;int index=-1;	   
			   int n=a.length;
			   
			   for(i=0;i<n-1;i++)
				   if(a[i]<a[i+1]) index=i;
			   
			   if(index==-1) return false;
			   i=index;

			  
			   for(j=i+1;j<n && a[i]<a[j];j++);

			   int temp=a[i];
			   a[i]=a[j-1];
			   a[j-1]=temp;
			   	   
			   for(int p=i+1,q=n-1;p<q;p++,q--)
			   {
				   temp=a[p];
				   a[p]=a[q];
				   a[q]=temp;
			   }
			   
			   return true;
		   }
		   
		   
		public static void division(char ch[],int divisor)
		   {
			   int div=Character.getNumericValue(ch[0]); int mul=10;int remainder=0;
			   StringBuilder quotient=new StringBuilder("");
			   for(int i=1;i<ch.length;i++)
			   {
				   div=div*mul+Character.getNumericValue(ch[i]);	
				   if(div<divisor) {quotient.append("0");continue;}
				   quotient.append(div/divisor);
				   div=div%divisor;mul=10;
				   
			   } 
			   remainder=div;
			   while(quotient.charAt(0)=='0')quotient.deleteCharAt(0);	   
			   System.out.println(quotient+" "+remainder);	  
		   }
		
		public static void sieve(int size)
		{
			sieve=new int[size+1];
			primes=new ArrayList<Integer>();
			sieve[1]=1;
			for(int i=2;i<=Math.sqrt(size);i++)
			{
				if(sieve[i]==0)
				 {
					for(int j=i*i;j<size;j+=i) sieve[j]=1;
				 }
			}
			
			for(int i=2;i<=size;i++)
			{
				if(sieve[i]==0) primes.add(i);
			}
		}
		
		public static long pow(long n, long b, long MOD)
		   {
		       long x=1;long y=n; 
		       while(b > 0)
		       {
		           if(b%2 == 1)
		           {
		               x=x*y;
		               if(x>MOD) x=x%(MOD);
		           }
		           y = y*y;
		           if(y>MOD) y=y%(MOD); 
		           b >>= 1;
		       }
		       return x;
		   }


		public static long mod_inv(long n,long mod)
		{
			return pow(n,mod-2,mod);
		}
		
		 public static int upper(Integer[] a,int start,int end,int key)
		 {
			   int mid=(start+end)>>1;
			   if(start==end && a[mid]<key) {return -1;}
			   if(start>end) return -1;

			   if(a[mid]>=key && (((mid-1)>=0 && a[mid-1]<key) || (mid-1)==0)) return mid;
			   else if(a[mid]== key && (mid-1)>=0 && a[mid-1]==key) return lower(a,start,mid-1,key);   
			   else if(key>a[mid]) return lower(a,mid+1,end,key);
			   else return lower(a,start,mid-1,key);
		}
		 
		 public static int lower(Integer a[],int start,int end,int key)
		 {
			   int mid=(start+end)>>1;
			   if(start==end && a[mid]>key) {return -1;}
			   if(start>end) return -1;

			   if(a[mid]<=key && (((mid+1)<a.length && a[mid+1]>key) || (mid+1)==a.length)) return mid;
			   else if(a[mid]== key && (mid+1)<a.length && a[mid+1]==key) return upper(a,mid+1,end,key);   
			   else if(key>=a[mid]) return upper(a,mid+1,end,key);
			   else return upper(a,start,mid-1,key);
		} 
		   
		public int gcd(int a,int b)
		{
			if(a==0) return b;
			return gcd(b%a,a);
		}
		public fast() {
			this(System.in);
		}
		public fast(InputStream is) {
			i = is;
		}
		public int read() {
			if (numChars == -1)
				throw new InputMismatchException();
			if (curChar >= numChars) {
				curChar = 0;
				try {
					numChars = i.read(buf);
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (numChars <= 0)
					return -1;
			}
			return buf[curChar++];
		}
		public String nextLine() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isEndOfLine(c));
			return res.toString();
		}
		public String nextString() {
     		int c = read();
			while (isSpaceChar(c))
				c = read();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isSpaceChar(c));
			return res.toString();
		}
		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 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 boolean isSpaceChar(int c) {
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}
		public boolean isEndOfLine(int c) {
			return c == '\n' || c == '\r' || c == -1;
		}

	}	
}