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.
//package codeforces.contest.c1491;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
import java.util.StringTokenizer;

/*
https://codeforces.com/problemset/problem/1491/C
1
10
1 1 2 2 3 3 1 1 2 2

1
2
2 3
 */
public class Task1491_C {

    static void solve() {
        int n = FS.nextInt();
        int[] s = FS.readArray(n);
        int[] p = new int[n];
        long ans = 0;

        for (int i = 0; i < n; i++) {
            if (s[i] > p[i]) {
                ans += s[i] - p[i] - 1;
            } else if (i != n - 1) {
                p[i + 1] += p[i] - s[i] + 1;
            }
            if (s[i] > n - i - 1) {
                s[i] = n - i - 1;
            }
            for (int j = 2; j <= s[i]; j++) {
                p[i + j] += 1;
            }
        }

        FS.pt.println(ans);
    }

    public static void main(String[] args) {
        int T = FS.nextInt();
        for (int tt = 0; tt < T; tt++) {
            solve();
        }
        FS.pt.close();
    }

    static class FS {
        private static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        private static StringTokenizer st = new StringTokenizer("");
        static PrintWriter pt = new PrintWriter(System.out);

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

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

        static int[] readArray(int n) {
            int[] a = new int[n];
            for (int i = 0; i < n; i++) a[i] = nextInt();
            return a;
        }

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

        static int[][] read2Array(int n, int m) {
            int[][] a = new int[n][m];
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < m; j++) {
                    a[i][j] = nextInt();
                }
            }
            return a;
        }

        static long[][] read2ArrayL(int n, int m) {
            long[][] a = new long[n][m];
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < m; j++) {
                    a[i][j] = nextLong();
                }
            }
            return a;
        }

        void printArr(long[] arr) {
            for (long value : arr) {
                pt.print(value);
                pt.print(" ");
            }
            pt.println();
        }

        static long[] readArrayL(int n) {
            long[] a = new long[n];
            for (int i = 0; i < n; i++) a[i] = nextLong();
            return a;
        }

        static void printArr(int[] arr) {
            for (int value : arr) {
                pt.print(value);
                pt.print(" ");
            }
            pt.println();
        }

        static void printArrL(long[] arr) {
            for (long value : arr) {
                pt.print(value);
                pt.print(" ");
            }
            pt.println();
        }

        static void print2Arr(int[][] arr, int n, int m) {
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < m; j++) {
                    pt.print(arr[i][j]);
                    pt.print(" ");
                }
                pt.println();
            }
            pt.println();
        }

        static void print2Arr(long[][] arr, int n, int m) {
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < m; j++) {
                    pt.print(arr[i][j]);
                    pt.print(" ");
                }
                pt.println();
            }
            pt.println();
        }

        static List<Long> readListLong(int n) {
            List<Long> list = new ArrayList<>(n);
            for (int i = 0; i < n; i++) {
                list.add(nextLong());
            }
            return list;
        }

        static List<Integer> readListInt(int n) {
            List<Integer> list = new ArrayList<>(n);
            for (int i = 0; i < n; i++) {
                list.add(nextInt());
            }
            return list;
        }

        static <T> void printList(List<T> list) {
            for (T value : list) {
                pt.print(value);
                pt.print(" ");
            }
            pt.println();
        }

        static void close() {
            pt.close();
        }

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

    static class Mat {
        public static long pow(long a, long exp) {
            return (long) Math.pow(a, exp);
        }
    }

    static class NumberTheory {
        public static boolean isPrime(long n) {
            if (n <= 1) return false;
            if (n < 4) return true;
            if (n % 2 == 0) return false;
            if (n % 3 == 0) return false;

            for (int i = 5, next = 2; i * i <= n; i += next, next = 6 - next)
                if (n % i == 0) return false;

            return true;
        }

        public static long gcd(long a, long b) {
            while (b != 0) {
                long tmp = a % b;
                a = b;
                b = tmp;
            }
            return a;
        }

        public static long lcm(long a, long b) {
            return a * b / gcd(a, b);
        }

        public static List<Long> primeFactors(long n) {
            List<Long> ans = new ArrayList<>();
            while (n % 2 == 0) {
                ans.add(2L);
                n /= 2;
            }

            // n must be odd at this point.  So we can
            // skip one element (Note i = i + 2)
            for (long i = 3; i <= Math.sqrt(n); i += 2) {
                // While i divides n, print i and divide n
                while (n % i == 0) {
                    ans.add(i);
                    n /= i;
                }
            }

            // This condition is to handle the case when
            // n is a prime number greater than 2
            if (n > 2) {
                ans.add(n);
            }
            return ans;
        }

        static long fact(long n) {
            if (n == 0 || n == 1) return 1L;
            long r = 1;
            for (int i = 1; i <= n; i++) {
                r *= i;
            }
            return r;
        }

        static long fact(long n, long mod) {
            if (n <= 1) return 1;
            long ans = 1;
            for (int i = 1; i <= n; i++) {
                ans = (ans * i) % mod;
            }
            return ans;
        }

        static long fastExp(long x, long n, long mod) {
            long ans = 1;
            while (n > 0) {
                if (n % 2 == 1) ans = (ans * x) % mod;
                x = (x * x) % mod;
                n /= 2;
            }
            return ans;
        }
    }

    static class BinarySearch {
        public static int lowerBound(int[] arr, int key) {
            int low = 0;
            int high = arr.length - 1;
            while (low < high) {
                int mid = low + (high - low) / 2;
                if (arr[mid] >= key) {
                    high = mid;
                } else {
                    low = mid + 1;
                }
            }
            return low;
        }

        public static int lowerBound(long[] arr, long key) {
            int low = 0;
            int high = arr.length - 1;
            while (low < high) {
                int mid = low + (high - low) / 2;
                if (arr[mid] >= key) {
                    high = mid;
                } else {
                    low = mid + 1;
                }
            }
            return low;
        }

        public static <T extends Comparable<T>> int lowerBound(List<T> arr, T key) {
            int low = 0;
            int high = arr.size() - 1;
            while (low < high) {
                int mid = low + (high - low) / 2;
                if (arr.get(mid).compareTo(key) >= 0) {
                    high = mid;
                } else {
                    low = mid + 1;
                }
            }
            return low;
        }

        public static int upperBound(int[] arr, int key) {
            int low = 0;
            int high = arr.length - 1;
            while (low < high) {
                int mid = low + (high - low + 1) / 2;
                if (arr[mid] <= key) {
                    low = mid;
                } else {
                    high = mid - 1;
                }
            }
            return low;
        }

        public static int upperBound(long[] arr, long key) {
            int low = 0;
            int high = arr.length - 1;
            while (low < high) {
                int mid = low + (high - low + 1) / 2;
                if (arr[mid] <= key) {
                    low = mid;
                } else {
                    high = mid - 1;
                }
            }
            return low;
        }

        public static <T extends Comparable<T>> int upperBound(List<T> arr, T key) {
            int low = 0;
            int high = arr.size() - 1;
            while (low < high) {
                int mid = low + (high - low + 1) / 2;
                if (arr.get(mid).compareTo(key) >= 0) {
                    low = mid;
                } else {
                    high = mid - 1;
                }
            }
            return low;
        }
    }

    static class Pair<T, K> {
        T first;
        K second;

        public Pair(T first, K second) {
            this.first = first;
            this.second = second;
        }

        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;
            Pair<?, ?> pair = (Pair<?, ?>) o;
            return Objects.equals(first, pair.first) &&
                    Objects.equals(second, pair.second);
        }

        @Override
        public int hashCode() {
            return Objects.hash(first, second);
        }
    }
}
