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.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.InputMismatchException;
import java.util.*;
import java.io.*;
import java.lang.*;
public class Main{
    public static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private InputReader.SpaceCharFilter filter;
        private BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
     
        public InputReader(InputStream stream) {
            this.stream = stream;
        }
     
        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 String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            }
            catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
        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 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 double nextDouble() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            double res = 0;
            while (!isSpaceChar(c) && c != '.') {
                if (c == 'e' || c == 'E')
                    return res * Math.pow(10, nextInt());
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            }
            if (c == '.') {
                c = read();
                double m = 1;
                while (!isSpaceChar(c)) {
                    if (c == 'e' || c == 'E')
                        return res * Math.pow(10, nextInt());
                    if (c < '0' || c > '9')
                        throw new InputMismatchException();
                    m /= 10;
                    res += (c - '0') * m;
                    c = read();
                }
            }
            return res * sgn;
        }
     
        public String readString() {
            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 boolean isSpaceChar(int c) {
            if (filter != null)
                return filter.isSpaceChar(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 long gcd(long a, long b){
        if (a == 0)
            return b;  
        return gcd(b % a, a);  
    }
    static long lcm(long a, long b)  {
        return (a*b)/gcd(a, b);  
    }
    public static void sortbyColumn(int arr[][], int col) 
    { 
        
        Arrays.sort(arr, new Comparator<int[]>() { 
            
          @Override              
          
          public int compare(final int[] entry1,  
                             final int[] entry2) { 
  
            
            if (entry1[col] > entry2[col]) 
                return 1; 
            else
                return -1; 
          } 
        });  
    } 
    static long func(long a[],int size,int s){
        long max1=a[s];
        long maxc=a[s];
        for(int i=s+1;i<size;i++){
            maxc=Math.max(a[i],maxc+a[i]);
            max1=Math.max(maxc,max1);
        }
        return max1;
    }
    public static class Pair<U extends Comparable<U>, V extends Comparable<V>> implements Comparable<Pair<U, V>> {
        public U x;
        public V y;
    
        public Pair(U x, V y) {
            this.x = x;
            this.y = y;
        }
    
        public int hashCode() {
            return (x == null ? 0 : x.hashCode() * 31) + (y == null ? 0 : y.hashCode());
        }
    
        public boolean equals(Object o) {
            if (this == o)
                return true;
            if (o == null || getClass() != o.getClass())
                return false;
            Pair<U, V> p = (Pair<U, V>) o;
            return (x == null ? p.x == null : x.equals(p.x)) && (y == null ? p.y == null : y.equals(p.y));
        }
    
        public int compareTo(Pair<U, V> b) {
            int cmpU = x.compareTo(b.x);
            return cmpU != 0 ? cmpU : y.compareTo(b.y);
        }
    
        public String toString() {
            return String.format("(%s, %s)", x.toString(), y.toString());
        }
    
    }
    static class MultiSet<U extends Comparable<U>> {
        public int sz = 0;
        public TreeMap<U, Integer> t;
 
        public MultiSet() {
            t = new TreeMap<>();
        }
 
        public void add(U x) {
            t.put(x, t.getOrDefault(x, 0) + 1);
            sz++;
        }
 
        public void remove(U x) {
            if (t.get(x) == 1) t.remove(x);
            else t.put(x, t.get(x) - 1);
            sz--;
        }
 
    }
    static void shuffle(long[] a) {
        Random get = new Random();
        for (int i = 0; i < a.length; i++) {
            int r = get.nextInt(a.length);
            long temp = a[i];
            a[i] = a[r];
            a[r] = temp;
        }
    }
    static long myceil(long a, long b){
        return (a+b-1)/b;
    }
    
    static long C(long n,long r){
        long count=0,temp=n;
        long ans=1;
        long num=n-r+1,div=1;
        while(num<=n){
            ans*=num;
            //ans+=MOD;
            ans%=MOD;
            ans*=mypow(div,MOD-2);
            //ans+=MOD;
            ans%=MOD;
            num++;
            div++;
        }
        
        ans+=MOD;
        return ans%MOD;
    }
    static long fact(long a){
        long i,ans=1;
        for(i=1;i<=a;i++){
            ans*=i;
            ans%=MOD;
        }
        return ans%=MOD;
    }
    static void sieve(int n){
        is_sieve[0]=1;
        is_sieve[1]=1;
        int i,j,k;
        for(i=2;i<n;i++){
            if(is_sieve[i]==0){
                sieve[i]=i;
                tr.add(i);
                for(j=i*i;j<n;j+=i){
                    if(j>n||j<0){
                        break;
                    }
                    is_sieve[j]=1;
                    sieve[j]=i;
                }
            }
        }
    }
    static void calc(int n){
        int i,j;
        dp[n-1]=0;
        if(n>1)
        dp[n-2]=1;
        for(i=n-3;i>=0;i--){
            long ind=n-i-1;
            dp[i]=((ind*(long)mypow(10,ind-1))%MOD+dp[i+1])%MOD;
        }
    }
    static long mypow(long x,long y){
        long temp; 
        if( y == 0) 
            return 1; 
        temp = mypow(x, y/2); 
        if (y%2 == 0) 
            return (temp*temp)%MOD; 
        else
            return ((x*temp)%MOD*(temp)%MOD)%MOD; 
    }
    static long dist[],dp[];
    static int visited[];
    static ArrayList<Pair<Integer,String>> adj[];
    //static int dp[][][];
    static int R,G,B,MOD=1000000007;
    static int[] par,size,memo;
    static int[] sieve,is_sieve;
    static TreeSet<Integer> tr;
    static char ch[][], ch1[][];
    
    // static void lengen(int arr[],int ind){
    //     memo[ind]=Math.max(lengen(arr,ind+1),lis(arr,))
    // }
    static int lis(int arr[],int n,int ind,int cur){
        if(ind>=n){
            return memo[ind]=0; 
        }
        else if(ind>=0&&memo[ind]>-1){
            return memo[ind];
        }
        else if(cur<arr[ind+1]){
            return memo[ind]=Math.max(lis(arr,n,ind+1,arr[ind+1])+1,lis(arr,n,ind+1,cur));
        }else{
            return memo[ind]=lis(arr,n,ind+1,cur);
        }
    }
    
    
    
    public static void main(String args[]){
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter w = new PrintWriter(outputStream);
        int t,i,j,tno=0,tte;
        t=in.nextInt();
        //t=1;
        //tte=t;
        TreeSet<Integer> tr=new TreeSet<>();
        for(i=0;i<=30;i++){
            tr.add((int)mypow(2,i));
        }
        while(t-->0){
            int n=in.nextInt();
            int arr[]=new int[n];
            int cur[]=new int[n+1];
            for(i=0;i<n;i++){
                arr[i]=in.nextInt();
            }
            long ans=0;
            for(i=0;i<n;i++){
                int temp=cur[i];
                if(temp<arr[i]-1){
                    ans+=arr[i]-1-temp;
                    temp+=arr[i]-1-temp;
                }
                cur[i+1]+=temp-arr[i]+1;
                if(i+2<n){
                    for(j=i+2;j<Math.min(n,i+arr[i]+1);j++){
                        cur[j]++;
                    }
                }
            }
            w.println(ans);
        }
        w.close();
    }
}
