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.
# Fast IO Region
import os
import sys
from io import BytesIO, IOBase
BUFSIZE = 8192
class FastIO(IOBase):
    newlines = 0
    def __init__(self, file):
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None
    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()
    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()
    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)
class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode("ascii"))
        self.read = lambda: self.buffer.read().decode("ascii")
        self.readline = lambda: self.buffer.readline().decode("ascii")
sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip("\r\n")
# Get out of main function
def main():
    pass
# decimal to binary
def binary(n):
    return (bin(n).replace("0b", ""))
# binary to decimal
def decimal(s):
    return (int(s, 2))
# power of a number base 2
def pow2(n):
    p = 0
    while n > 1:
        n //= 2
        p += 1
    return (p)
# if  number is prime in √n time
def isPrime(n):
    if (n == 1):
        return (False)
    else:
        root = int(n ** 0.5)
        root += 1
        for i in range(2, root):
            if (n % i == 0):
                return (False)
        return (True)
# list to string ,no spaces
def lts(l):
    s = ''.join(map(str, l))
    return s
# String to list
def stl(s):
    # for each character in string to list with no spaces -->
    l = list(s)
    # for space in string  -->
    # l=list(s.split(" "))
    return l
# Returns list of numbers with a particular sum
def sq(a, target, arr=[]):
    s = sum(arr)
    if (s == target):
        return arr
    if (s >= target):
        return
    for i in range(len(a)):
        n = a[i]
        remaining = a[i + 1:]
        ans = sq(remaining, target, arr + [n])
        if (ans):
            return ans
# Sieve for prime numbers in a range
def SieveOfEratosthenes(n):
    cnt = 0
    prime = [True for i in range(n + 1)]
    p = 2
    while (p * p <= n):
        if (prime[p] == True):
            for i in range(p * p, n + 1, p):
                prime[i] = False
        p += 1
    for p in range(2, n + 1):
        if prime[p]:
            cnt += 1
            # print(p)
    return (cnt)
# for positive integerse only
def nCr(n, r):
    f = math.factorial
    return f(n) // f(r) // f(n - r)
# 1000000007
mod = int(1e9) + 7
def ssinp(): return input()
# s=input()
def iinp(): return int(input())
# n=int(input())
def nninp(): return map(int, input().split())
# a,b,c=map(int,input().split())
def llinp(): return list(map(int, input().split()))
# a=list(map(int,input().split()))
def p(xyz): print(xyz)
def p2(a, b): print(a, b)
import math
# import random
# sys.setrecursionlimit(300000)
# from fractions import Fraction
#from collections import OrderedDict
# from collections import deque
########################                         mat=[[0 for i in range(n)] for j in range(m)]                      ########################
########################                         list.sort(key=lambda x:x[1]) for sorting a list according to second element in sublist            ########################
########################                         Speed: STRING < LIST < SET,DICTIONARY                      ########################
########################                         from collections import deque                              ########################
########################                         ASCII of A-Z= 65-90                                        ########################
########################                         ASCII of a-z= 97-122                                       ########################
########################                         d1.setdefault(key, []).append(value)                       ########################
for __ in range(iinp()):
    n=iinp()
    tramp=llinp()
    cnt=[0]*(n+2)
    ans=0
    for i in range(n):
        if(tramp[i]-cnt[i]>1):
            ans+=tramp[i]-(cnt[i]+1)
        for j in range(i+2,min(n,i+tramp[i]+1),1):
            cnt[j]+=1
        if(cnt[i]>=tramp[i]-1):
            cnt[i+1]+=cnt[i]-(tramp[i]-1)
    p(ans)

