Awruk is taking part in elections in his school. It is the final round. He has only one opponent — Elodreip. The are n students in the school. Each student has exactly k votes and is obligated to use all of them. So Awruk knows that if a person gives a_i votes for Elodreip, than he will get exactly k - a_i votes from this person. Of course 0 ≤ k - a_i holds.

Awruk knows that if he loses his life is over. He has been speaking a lot with his friends and now he knows a_1, a_2, ..., a_n — how many votes for Elodreip each student wants to give. Now he wants to change the number k to win the elections. Of course he knows that bigger k means bigger chance that somebody may notice that he has changed something and then he will be disqualified.

So, Awruk knows a_1, a_2, ..., a_n — how many votes each student will give to his opponent. Help him select the smallest winning number k. In order to win, Awruk needs to get strictly more votes than Elodreip.

Input

The first line contains integer n (1 ≤ n ≤ 100) — the number of students in the school.

The second line contains n integers a_1, a_2, …, a_n (1 ≤ a_i ≤ 100) — the number of votes each student gives to Elodreip.

Output

Output the smallest integer k (k ≥ max a_i) which gives Awruk the victory. In order to win, Awruk needs to get strictly more votes than Elodreip.

Examples

Input

5
1 1 1 5 1


Output

5

Input

5
2 2 3 2 2


Output

5

Note

In the first example, Elodreip gets 1 + 1 + 1 + 5 + 1 = 9 votes. The smallest possible k is 5 (it surely can't be less due to the fourth person), and it leads to 4 + 4 + 4 + 0 + 4 = 16 votes for Awruk, which is enough to win.

In the second example, Elodreip gets 11 votes. If k = 4, Awruk gets 9 votes and loses to Elodreip.
//Author: Mo Abjal, MJP Rohilkhand University Bareilly, UP, India 2018.
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/////////////////////////////////////////*     S0LUT10N     *//////////////////////////////////////////////
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//mahnazanwar
//mahnaz1641
// 743545
import java.util.*;
import java.io.*;
import java.text.*;
import java.math.*;
public class Main{
	public static StringTokenizer token = new StringTokenizer("");
	public static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	public static PrintWriter output = new PrintWriter(System.out);
	public static void main(String[] afzal) throws Exception {		
		int N = ni();
		Integer A[] = ai(N);
		Arrays.sort(A);
		int max = A[N-1];
		long sum=0;
		for(int i=0;i<N;i++){
			sum+=A[i];
		}
		while(true){
			long temp=0;
			for(int i=0;i<N;i++){
				temp+=max-A[i];
			}
			if(temp>sum){
				output.println(max); break;
			}
			max++;
		}
		output.close();
		/*int T = ni();
		for(int i=0;i<T;i++){
			int N = ni();
			int M = ni();
			char C[][] = new char[N][M];
			for(int j=0;j<N;j++){
				String s = ns();
				char S[] = s.toCharArray();
				for(int k=0;k<M;k++){
					C[j][k] = S[k];
				}
			}
			int count=0;
			for(int j=0;j<N;j++){
				for(int k=0;k<M;k++){
					if(C[j][k]=='.') count++;
				}
			}
			for(int j=0;j<N-1;j++){
				for(int k=0;k<M-1;k++){
					char a = C[j][k];
					char b = C[j][k+1];
					char c = C[j+1][k];
					char d = C[j+1][k+1];
					if((a=='.' || a=='c') && (b=='.' || b=='c') && (c=='.' || c=='c') && (d=='.' || d=='c')){
						C[j][k] = 'c';
						C[j][k+1] = 'c';
						C[j+1][k] = 'c';
						C[j+1][k+1] = 'c';
					}
				}
			}
			//output.println();
			int temp=0;
			for(int j=0;j<N;j++){
				for(int k=0;k<M;k++){
					if(C[j][k]=='c') temp++;
					//output.print(C[j][k]);
				}
				//output.println();
			}
			//output.println(count+" "+temp);
			if(temp==count) output.println("YES"); else output.println("NO");
		}
		output.close();*/
	}
	public static String pc(char c){
		return Character.toString(c);
	} 
	public static Integer pci(char c){
		return pi(Character.toString(c));
	}
	public static Integer pi(String str){
		return Integer.parseInt(str);
	}
	public static Long pl(String str){
		return Long.parseLong(str);
	}
	public static String ps(Integer N){
		return Integer.toString(N);
	}
	public static char[] pcc(String str){
		return str.toCharArray();
	}
	public static Integer ni() throws IOException{
		if(!token.hasMoreElements()){
			token = new StringTokenizer(br.readLine());
		}
		return Integer.parseInt(token.nextToken());
	}
	public static Long nl() throws IOException{
		if(!token.hasMoreElements()){
			token = new StringTokenizer(br.readLine());
		}
		return Long.parseLong(token.nextToken());
	}
	public static Double nd() throws IOException{
		if(!token.hasMoreElements()){
			token = new StringTokenizer(br.readLine());
		}
		return Double.parseDouble(token.nextToken());
	}
	public static String ns() throws IOException{
		if(!token.hasMoreElements()){
			token = new StringTokenizer(br.readLine());
		}
		return token.nextToken();
	}
	public static Integer[] ai(int N) throws IOException{
		Integer A[] = new Integer[N];
		token = new StringTokenizer(br.readLine());
		for(int i=0;i<A.length;i++){
			A[i] = pi(token.nextToken());
		}
		return A;
	}
	public static long[] al(int N) throws IOException{
		long A[] = new long[N];
		token = new StringTokenizer(br.readLine());
		for(int i=0;i<N;i++){
			A[i] = Long.parseLong(token.nextToken());
		}
		return A;
	}
	public static char[][] acc(int N,int M) throws IOException{
		char C[][] = new char[N][M];
		for(int i=0;i<N;i++){
			token = new StringTokenizer(br.readLine());
			String s = token.nextToken();
			for(int j=0;j<M;j++){
				C[i][j] = s.charAt(j);
			}
		}
		return C;
	}
	public static String[] as(int N) throws IOException{
		String S[] = new String[N];
		token = new StringTokenizer(br.readLine());
		for(int i=0;i<S.length;i++){
			S[i] = token.nextToken();
		}
		return S;
	}
	public static double ncr(int n, int r){
		if(n==r) return 1;
		else
		return (fact(n)/(fact(r)*fact(n-r)));
	}
	public static long fact(long N){
		long fact = 1;
		for(int i=1;i<=N;i++){
			fact = fact * i;
		}
		return fact;
	}
	public static BigInteger factB(int N){
		BigInteger b = new BigInteger("1");
		for(int i=1;i<=N;i++){
			b = b.multiply(BigInteger.valueOf(i));
		}
		return b;
	}
	public static long sod(long N){
		long sum = 0;
		while(N>0){
			long x = N%10;
			sum = sum + x;
			N = N/10;
		}
		return sum;
	}
	public static Integer cd(long N){
		int count=0;
		while(N>0){
			N = N/10; count++;
		}
		return count=0;
	}
}
class Pair implements Comparable{
	int a,b;
	public Pair(int a,int b){
		this.a = a;
		this.b = b;
	}
	public int compareTo(Object p){
		Pair pa = (Pair)p;
		//if(this.a==pa.a) return this.b - pa.b;
		return this.a - pa.a;
	} 
}class Pair3 implements Comparable{
	int a,b,c;
	public Pair3(int a,int b,int c){
		this.a = a;
		this.b = b;
		this.c = c;
	}
	public int compareTo(Object p){
		Pair pa = (Pair)p;
		//if(this.a==pa.a) return this.b - pa.b;
		return this.a - pa.a;
	} 
}
//Copyright Reserved - Mo Abjal.
