There is a trampoline park with n trampolines in a line. The i-th of which has strength S_i.

Pekora can jump on trampolines in multiple passes. She starts the pass by jumping on any trampoline of her choice. 

If at the moment Pekora jumps on trampoline i, the trampoline will launch her to position i + S_i, and S_i will become equal to max(S_i-1,1). In other words, S_i will decrease by 1, except of the case S_i=1, when S_i will remain equal to 1. 

If there is no trampoline in position i + S_i, then this pass is over. Otherwise, Pekora will continue the pass by jumping from the trampoline at position i + S_i by the same rule as above.

Pekora can't stop jumping during the pass until she lands at the position larger than n (in which there is no trampoline). Poor Pekora!

Pekora is a naughty rabbit and wants to ruin the trampoline park by reducing all S_i to 1. What is the minimum number of passes she needs to reduce all S_i to 1?

Input

The first line contains a single integer t (1 ≤ t ≤ 500) — the number of test cases.

The first line of each test case contains a single integer n (1 ≤ n ≤ 5000) — the number of trampolines.

The second line of each test case contains n integers S_1, S_2, ..., S_n (1 ≤ S_i ≤ 10^9), where S_i is the strength of the i-th trampoline.

It's guaranteed that the sum of n over all test cases doesn't exceed 5000.

Output

For each test case, output a single integer — the minimum number of passes Pekora needs to do to reduce all S_i to 1.

Example

Input


3
7
1 4 2 2 2 2 2
2
2 3
5
1 1 1 1 1


Output


4
3
0

Note

For the first test case, here is an optimal series of passes Pekora can take. (The bolded numbers are the positions that Pekora jumps into during these passes.)

  * [1,4,2,2,2,2,2] 
  * [1,4,1,2,1,2,1] 
  * [1,3,1,2,1,1,1] 
  * [1,2,1,2,1,1,1] 



For the second test case, the optimal series of passes is show below.

  * [2,3] 
  * [1,3] 
  * [1,2] 



For the third test case, all S_i are already equal to 1.
import java.io.*;
import java.util.*;
import java.math.*;
import java.math.BigInteger; 
//import javafx.util.*; 
public final class B
{    
	static StringBuilder ans=new StringBuilder();
	static FastReader in=new FastReader();
	static ArrayList<ArrayList<Integer>> g,CARS,intersection;	
	static long mod=1000000007;
	static int D1[],D2[],par[];
	static boolean set[];
	static long INF=Long.MAX_VALUE;
	public static void main(String args[])throws IOException
	{  		

		int T=i();
		while(T-->0)
		{
			int N=i(); 
			long A[]=new long[N];
			for(int i=0; i<N; i++)
			{
				A[i]=l()-1;
			}
			long jumps[]=new long[N+1];
			long max=0;
			for(int i=0; i<N; i++)
			{
				if(jumps[i]<=A[i])
				{
					//System.out.println("At --> "+i+" "+(A[i]-jumps[i]));
					max+=A[i]-jumps[i];
					jumps[i]=A[i];
					for(int j=i+2; j<Math.min(jumps[i]+i+2, N); j++)
					{
						jumps[j]++;
					}
				}
				else
				{
					for(int j=i+2; j<Math.min(A[i]+i+2, N); j++)
					{
						jumps[j]++;
					}
					jumps[i+1]+=jumps[i]-A[i];
				}				
				
				//print(jumps);
			}
			System.out.println(max);
			
		}
		
	}


	static long min(long a,long b,long c)
	{
		return Math.min(a, Math.min(c, b));
	}
	static void dfs(int n)
	{
		set[n]=true;
		for(int c:g.get(n))
		{
			if(!set[c])dfs(c);
		}
	}
	static void print(int a)
	{
		System.out.println("! "+a);
	}
	static int ask(int a,int b)
	{
		System.out.println("? "+a+" "+b);
		return i();
	}
	static int find(int a)
	{
		if(par[a]<0)return a;
		return par[a]=find(par[a]);
	}
	static void union(int a,int b)
	{
		a=find(a);
		b=find(b);
		if(a!=b)
		{
			par[a]+=par[b]; //transfers the size
			par[b]=a;       //changes the parent
		}
	}
	static ArrayList<Integer> IND(int B[],HashMap<Integer,Integer> mp)
	{
		ArrayList<Integer> A=new ArrayList<>();
		for(int i:B)
		{
			if(mp.containsKey(i))
			{
				A.add(i);
				int f=mp.get(i)-1;
				if(f==0)
					mp.remove(i);
				else mp.put(i, f);		
			}
		}
		return A;
	}
	static HashMap<Integer,Integer> hash(int A[],int index)
	{
		HashMap<Integer,Integer> mp=new HashMap<Integer,Integer>();
		for(int i=index; i<A.length; i++)
		{
			int f=mp.getOrDefault(A[i], 0)+1;
			mp.put(A[i], f);
		}
		return mp;
	}
	static void swap(char A[],int a,int b)
	{
		char ch=A[a];
		A[a]=A[b];
		A[b]=ch;
	}

	static long lower_Bound(long A[],int low,int high, long x) 
	{ 
		if (low > high) 
			if (x >= A[high]) 
				return A[high]; 

		int mid = (low + high) / 2; 

		if (A[mid] == x) 
			return A[mid]; 

		if (mid > 0 && A[mid - 1] <= x && x < A[mid]) 
			return A[mid - 1]; 

		if (x < A[mid]) 
			return lower_Bound( A, low, mid - 1, x); 

		return lower_Bound(A, mid + 1, high, x); 
	} 
	static void sort(long[] a) //check for long
	{
		ArrayList<Long> l=new ArrayList<>();
		for (long i:a) l.add(i);
		Collections.sort(l);
		for (int i=0; i<a.length; i++) a[i]=l.get(i);
	}
	static void setGraph(int N)
	{
		g=new ArrayList<ArrayList<Integer>>();
		intersection=new ArrayList<ArrayList<Integer>>();
		CARS=new ArrayList<ArrayList<Integer>>();
		for(int i=0; i<=N; i++)
		{
			CARS.add(new ArrayList<Integer>());
			intersection.add(new ArrayList<Integer>());
			g.add(new ArrayList<Integer>());

		}
	}

	static  long pow(long a,long b)
	{
		long mod=1000000007;
		long pow=1;
		long x=a;
		while(b!=0)
		{
			if((b&1)!=0)pow=(pow*x)%mod;
			x=(x*x)%mod;
			b/=2;
		}
		return pow;
	}
	static long toggleBits(long x)//one's complement || Toggle bits
	{
		int n=(int)(Math.floor(Math.log(x)/Math.log(2)))+1;

		return ((1<<n)-1)^x;
	}
	static int countBits(long a)
	{
		return (int)(Math.log(a)/Math.log(2)+1);
	}
	static void sort(int[] a) {
		ArrayList<Integer> l=new ArrayList<>();
		for (int i:a) l.add(i);
		Collections.sort(l);
		for (int i=0; i<a.length; i++) a[i]=l.get(i);
	}
	static boolean isPrime(long N)
	{
		if (N<=1)  return false; 
		if (N<=3)  return true; 
		if (N%2 == 0 || N%3 == 0) return false; 
		for (int i=5; i*i<=N; i=i+6) 
			if (N%i == 0 || N%(i+2) == 0) 
				return false; 
		return true; 
	}
	static long GCD(long a,long b) 
	{
		if(b==0)
		{
			return a;
		}
		else return GCD(b,a%b );
	}

	//Debugging Functions Starts

	static void print(char A[])
	{
		for(char c:A)System.out.print(c+" ");
		System.out.println();
	}
	static void print(boolean A[])
	{
		for(boolean c:A)System.out.print(c+" ");
		System.out.println();
	}
	static void print(int A[])
	{
		for(int a:A)System.out.print(a+" ");
		System.out.println();	
	}
	static void print(long A[])
	{
		for(long i:A)System.out.print(i+ " ");
		System.out.println();

	}
	static void print(ArrayList<Integer> A)
	{
		for(int a:A)System.out.print(a+" ");
		System.out.println();
	}

	//Debugging Functions END
	//----------------------
	//IO FUNCTIONS STARTS
	static HashMap<Integer,Integer> Hash(int A[])
	{
		HashMap<Integer,Integer> mp=new HashMap<>();
		for(int a:A)
		{
			int f=mp.getOrDefault(a,0)+1;
			mp.put(a, f);
		}
		return mp;
	}
	static int i()
	{
		return in.nextInt();
	}

	static long l()
	{
		return in.nextLong();
	}

	static int[] input(int N){
		int A[]=new int[N];
		for(int i=0; i<N; i++)
		{
			A[i]=in.nextInt();
		}
		return A;
	}

	static long[] inputLong(int N)     {
		long A[]=new long[N];
		for(int i=0; i<A.length; i++)A[i]=in.nextLong();
		return A;
	}

	//IO FUNCTIONS END

}
class height implements Comparable<height>
{
	long h,w; int index;
	height(long h,long w,int index)
	{
		this.h=h;
		this.index=index;
		this.w=w;
	}
	public int compareTo(height X)
	{
		if(this.h>X.h)return 1;
		else if(this.h<X.h)return -1;
		else {
			if(this.w>X.w)return 1;
			else if(this.w<X.w)return -1;
			else return 0;
		}
	}
}
class width implements Comparable<width>
{
	long h,w; int index;
	width(long h,long w,int index)
	{
		this.h=h;
		this.index=index;
		this.w=w;
	}
	public int compareTo(width X)
	{
		if(this.w>X.w)return 1;
		else if(this.w<X.w)return -1;
		else 
		{
			if(this.h>X.h)return 1;
			else if(this.h<X.h)return -1;
			else return 0;
		}
	}
}

//Code For FastReader
//Code For FastReader
//Code For FastReader
//Code For FastReader
class FastReader
{
	BufferedReader br;
	StringTokenizer st;
	public FastReader()
	{
		br=new BufferedReader(new InputStreamReader(System.in));
	}

	String next()
	{
		while(st==null || !st.hasMoreElements())
		{
			try
			{
				st=new StringTokenizer(br.readLine());
			}
			catch(IOException e)
			{
				e.printStackTrace();
			}
		}
		return st.nextToken();
	}

	int nextInt()
	{
		return Integer.parseInt(next());
	}

	long nextLong()
	{
		return Long.parseLong(next());
	}

	double nextDouble()
	{
		return Double.parseDouble(next());
	}

	String nextLine()
	{
		String str="";
		try
		{
			str=br.readLine();
		}
		catch (IOException e)
		{
			e.printStackTrace();
		}
		return str;
	}

}