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.util.*;
import java.io.*;
import java.lang.reflect.Array;

		public class codeforces
		{	
			public static void main(String[] args)
			{
				InputReader in = new InputReader(System.in);
				PrintWriter pw = new PrintWriter(System.out);
			
				int n = in.nextInt();
				String s = in.nextLine();
				Stack<Character> stack = new Stack<>();
				Stack<Integer> stack_p = new Stack<>();
				
				for(int i=0;i<n;i++)
				{
					if(stack.isEmpty())
					{
						stack.push(s.charAt(i));
						stack_p.push(i);
					}
					else 
					{
						if(stack.peek() == '(' && s.charAt(i) == ')')
						{
							stack.pop();
							stack_p.pop();
						}
						else
						{
							stack.push(s.charAt(i));
							stack_p.push(i);
						}
					}
				}
				
				//pw.println(stack);
				int ans = 0;
				
				if(stack.size() == 2 && stack.pop() == stack.peek())
				{
					char c = stack.peek();
					
					if(c == '(')
					{
						for(int i=stack_p.peek();i<n;i++)
						{
							if(s.charAt(i) == c)
								ans++;
						}
					}
					else
					{
						stack_p.pop();
					
						for(int i=0;i<=stack_p.peek();i++)
						{
							if(s.charAt(i) == c)
								ans++;
						}
					}
				}
				
				pw.println(ans);
				
				pw.flush();
				pw.close();
			}
			
			public static ArrayList Divisors(int n)
			{
			    ArrayList<Integer> div = new ArrayList<>();
			    
			    for (int i=1; i<=Math.sqrt(n); i++)
			    {
			        if (n%i == 0)
			        {
			        	div.add(i);
			                
			            if(n/i != i)
			            	div.add(n/i);
			        }
			    }
			    return div;
			}
			
			/*public static void DFS(int s)
			{
				int count = 0;
				visited[s] = true;
				
				for(int u : adj[s])
				{
					if(!visited[u])
					{
						count++;
						DFS(u);
					}
				}
				
				if(s == 1 && count == 1)
					leaf++;
				
				if(count == 0)
					leaf++;
			}*/
			
			public static int BinarySearch(long[] a, long k)
			{
				int n = a.length;
				int i = 0, j = n-1;
				int mid = 0;
				
				if(k < a[0])
					return 0;
				else if(k >= a[n-1])
					return n;
				else
				{
					while(j - i > 1)
					{
						mid = (i+j)/2;
						
						if(k >= a[mid])
							i = mid;
						else
							j = mid;
					}
				}
				
				return i+1;
			}
			public static long GCD(long a,long b)
			{
				if(b==0)
					return a;
				else
					return GCD(b,a%b);
			}
			
			static class pair implements Comparable<pair>
			{
				Integer x, y;
				pair(int x,int y)
				{
					this.x=x;
					this.y=y;
				}
				
				public int compareTo(pair o) {
					int result = x.compareTo(o.x);
					if(result==0)
						result = y.compareTo(o.y);
					
					return result;
				}  
				
				public String toString()
				{
					return x+" "+y;
				}
				
				public boolean equals(Object o)
				{
					if (o instanceof pair)
				    {
						pair p = (pair)o;
						return p.x - x == 0 && p.y - y == 0 ;
					}
					return false;
				}
				
				public int hashCode()
				{
					return new Long(x).hashCode()*31 + new Long(y).hashCode();
				}
			}
			
			static class InputReader 
			{
				 
				private final InputStream stream;
				private final byte[] buf = new byte[8192];
				private int curChar, snumChars;
				private SpaceCharFilter filter;
		 
				public InputReader(InputStream stream) 
				{
					this.stream = stream;
				}
		 
				public int snext() 
				{
					if (snumChars == -1)
						throw new InputMismatchException();
					if (curChar >= snumChars) 
					{
						curChar = 0;
						try 
						{
							snumChars = stream.read(buf);
						} 
						catch (IOException e) 
						{
							throw new InputMismatchException();
						}
						if (snumChars <= 0)
							return -1;
					}
					return buf[curChar++];
				}
		 
				public int nextInt() 
			    {
					int c = snext();
					while (isSpaceChar(c)) 
					{
						c = snext();
					}
					int sgn = 1;
					if (c == '-')
				    {
						sgn = -1;
						c = snext();
					}
					int res = 0;
					do 
					{
						if (c < '0' || c > '9')
							throw new InputMismatchException();
						res *= 10;
						res += c - '0';
						c = snext();
					} while (!isSpaceChar(c));
					return res * sgn;
				}
		 
				public long nextLong()
			    {
					int c = snext();
					while (isSpaceChar(c)) 
					{
						c = snext();
					}
					int sgn = 1;
					if (c == '-') 
					{
						sgn = -1;
						c = snext();
					}
					long res = 0;
					do 
					{
						if (c < '0' || c > '9')
							throw new InputMismatchException();
						res *= 10;
						res += c - '0';
						c = snext();
					} while (!isSpaceChar(c));
					return res * sgn;
				}
		 
				public int[] nextIntArray(int n) 
				{
					int a[] = new int[n];
					for (int i = 0; i < n; i++) 
					{
						a[i] = nextInt();
					}
					return a;
				}
		 
				public String readString()
			    {
					int c = snext();
					while (isSpaceChar(c)) 
					{
						c = snext();
					}
					StringBuilder res = new StringBuilder();
					do 
					{
						res.appendCodePoint(c);
						c = snext();
					} while (!isSpaceChar(c));
					return res.toString();
				}
		 
				public String nextLine() 
				{
					int c = snext();
					while (isSpaceChar(c))
						c = snext();
					StringBuilder res = new StringBuilder();
					do 
					{
						res.appendCodePoint(c);
						c = snext();
					} while (!isEndOfLine(c));
					return res.toString();
				}
		 
				public boolean isSpaceChar(int c) 
				{
					if (filter != null)
						return filter.isSpaceChar(c);
					return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
				}
		 
				private boolean isEndOfLine(int c) 
				{
					return c == '\n' || c == '\r' || c == -1;
				}
		 
				public interface SpaceCharFilter
			    {
					public boolean isSpaceChar(int ch);
				}
			}
			
			static class CodeX {
	        public static void sort(long arr[]) {
	            merge_sort(arr, 0, arr.length - 1);
	        }
	
	        private static void merge_sort(long A[], long start, long end) {
	            if (start < end) {
	                long mid = (start + end) / 2;
	                merge_sort(A, start, mid);
	                merge_sort(A, mid + 1, end);
	                merge(A, start, mid, end);
	            }
	
	        }
	
	        private static void merge(long A[], long start,long mid, long end) {
	            long p = start, q = mid + 1;
	            long Arr[] = new long[(int)(end - start + 1)];
	            long k = 0;
	
	            for (int i = (int)start; i <= end; i++) {
	                if (p > mid)
	                    Arr[(int)k++] = A[(int)q++];
	
	                else if (q > end)
	                    Arr[(int)k++] = A[(int)p++];
	
	                else if (A[(int)p] < A[(int)q])
	                    Arr[(int)k++] = A[(int)p++];
	
	                else
	                    Arr[(int)k++] = A[(int)q++];
	            }
	            for (int i = 0; i < k; i++) {
	                A[(int)start++] = Arr[i];
	            }
	
	        }
	
	    }
		}	
		

			