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.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;
import java.util.TreeMap;

public class Main implements Runnable {
    int n, m;
    static boolean use_n_tests = true;

    void solve(FastScanner in, PrintWriter out, int testNumber) {
        n = in.nextInt();
        long[] s = in.nextArrayL(n);
        long ans = 0;
        long[] level = new long[n];
        for (int i = 0; i < n; i++) {
            long have = level[i];
            long need = s[i] - 1;
            if (need > have) {
                ans += need - have;
                level[i] += need - have;
            }
            for (int j = i + 2; j < Math.min(n, i + s[i] + 1); j++) {
                level[j]++;
            }
            level[i] -= (s[i] - 1);
            if (i + 1 < n && level[i] > 0) {
                level[i + 1] += level[i];
                level[i] = 0;
            }
        }
        out.println(ans);
    }

    // ****************************** template code ***********

    List<Integer> generatePrimes(int n) {
        List<Integer> res = new ArrayList<>();
        boolean[] sieve = new boolean[n + 1];
        for (int i = 2; i <= n; i++) {
            if (!sieve[i]) {
                res.add(i);
            }
            if ((long) i * i <= n) {
                for (int j = i * i; j <= n; j += i) {
                    sieve[j] = true;
                }
            }
        }
        return res;
    }

    int ask(int l, int r) {
        if (l >= r) {
            return -1;
        }
        System.out.printf("? %d %d\n", l + 1, r + 1);
        System.out.flush();
        return in.nextInt() - 1;
    }

    static int stack_size = 1 << 27;

    class Mod {
        long mod;

        Mod(long mod) {
            this.mod = mod;
        }

        long add(long a, long b) {
            a = mod(a);
            b = mod(b);
            return (a + b) % mod;
        }

        long sub(long a, long b) {
            a = mod(a);
            b = mod(b);
            return (a - b + mod) % mod;
        }

        long mul(long a, long b) {
            a = mod(a);
            b = mod(b);
            return a * b % mod;
        }

        long div(long a, long b) {
            a = mod(a);
            b = mod(b);
            return (a * inv(b)) % mod;
        }

        public long inv(long r) {
            if (r == 1)
                return 1;
            return ((mod - mod / r) * inv(mod % r)) % mod;
        }

        private long mod(long a) {
            return a % mod;
        }
    }

    class Coeff {
        long mod;
        long[][] C;
        long[] fact;
        boolean cycleWay = false;

        Coeff(int n, long mod) {
            this.mod = mod;
            fact = new long[n + 1];
            fact[0] = 1;
            for (int i = 1; i <= n; i++) {
                fact[i] = i;
                fact[i] %= mod;
                fact[i] *= fact[i - 1];
                fact[i] %= mod;
            }
        }

        Coeff(int n, int m, long mod) {
            // n > m
            cycleWay = true;
            this.mod = mod;
            C = new long[n + 1][m + 1];
            for (int i = 0; i <= n; i++) {
                for (int j = 0; j <= Math.min(i, m); j++) {
                    if (j == 0 || j == i) {
                        C[i][j] = 1;
                    } else {
                        C[i][j] = C[i - 1][j - 1] + C[i - 1][j];
                        C[i][j] %= mod;
                    }
                }
            }
        }

        public long C(int n, int m) {
            if (cycleWay) {
                return C[n][m];
            }
            return fC(n, m);
        }

        private long fC(int n, int m) {
            return (fact[n] * inv(fact[n - m] * fact[m] % mod)) % mod;
        }

        private long inv(long r) {
            if (r == 1)
                return 1;
            return ((mod - mod / r) * inv(mod % r)) % mod;
        }
    }

    class Pair {
        int first;
        int second;

        public int getFirst() {
            return first;
        }

        public int getSecond() {
            return second;
        }
    }

    class MultisetTree<T> {
        int size = 0;

        TreeMap<T, Integer> mp = new TreeMap<>();

        void add(T x) {
            mp.merge(x, 1, Integer::sum);
            size++;
        }

        void remove(T x) {
            if (mp.containsKey(x)) {
                mp.merge(x, -1, Integer::sum);
                if (mp.get(x) == 0) {
                    mp.remove(x);
                }
                size--;
            }
        }

        boolean contains(T x) {
            return mp.containsKey(x);
        }

        T greatest() {
            return mp.lastKey();
        }

        T smallest() {
            return mp.firstKey();
        }

        int size() {
            return size;
        }

        int diffSize() {
            return mp.size();
        }
    }

    class Multiset<T> {
        int size = 0;

        Map<T, Integer> mp = new HashMap<>();

        void add(T x) {
            mp.merge(x, 1, Integer::sum);
            size++;
        }

        boolean contains(T x) {
            return mp.containsKey(x);
        }

        void remove(T x) {
            if (mp.containsKey(x)) {
                mp.merge(x, -1, Integer::sum);
                if (mp.get(x) == 0) {
                    mp.remove(x);
                }
                size--;
            }
        }

        int size() {
            return size;
        }

        int diffSize() {
            return mp.size();
        }
    }

    static class Range {
        int l, r;
        int id;

        public int getL() {
            return l;
        }

        public int getR() {
            return r;
        }

        public Range(int l, int r, int id) {
            this.l = l;
            this.r = r;
            this.id = id;
        }
    }

    static class Array {
        static Range[] readRanges(int n, FastScanner in) {
            Range[] result = new Range[n];
            for (int i = 0; i < n; i++) {
                result[i] = new Range(in.nextInt(), in.nextInt(), i);
            }
            return result;
        }

        static List<List<Integer>> intInit2D(int n) {
            List<List<Integer>> res = new ArrayList<>();
            for (int i = 0; i < n; i++) {
                res.add(new ArrayList<>());
            }
            return res;
        }

        static boolean isSorted(Integer[] a) {
            for (int i = 0; i < a.length - 1; i++) {
                if (a[i] > a[i + 1]) {
                    return false;
                }
            }
            return true;
        }

        static public long sum(int[] a) {
            long sum = 0;
            for (int x : a) {
                sum += x;
            }
            return sum;
        }

        static public long sum(long[] a) {
            long sum = 0;
            for (long x : a) {
                sum += x;
            }
            return sum;
        }

        static public long sum(Integer[] a) {
            long sum = 0;
            for (int x : a) {
                sum += x;
            }
            return sum;
        }

        static public int min(Integer[] a) {
            int mn = Integer.MAX_VALUE;
            for (int x : a) {
                mn = Math.min(mn, x);
            }
            return mn;
        }

        static public int min(int[] a) {
            int mn = Integer.MAX_VALUE;
            for (int x : a) {
                mn = Math.min(mn, x);
            }
            return mn;
        }

        static public int max(Integer[] a) {
            int mx = Integer.MIN_VALUE;
            for (int x : a) {
                mx = Math.max(mx, x);
            }
            return mx;
        }

        static public int max(int[] a) {
            int mx = Integer.MIN_VALUE;
            for (int x : a) {
                mx = Math.max(mx, x);
            }
            return mx;
        }

        static public int[] readint(int n, FastScanner in) {
            int[] out = new int[n];
            for (int i = 0; i < out.length; i++) {
                out[i] = in.nextInt();
            }
            return out;
        }
    }

    class Graph {
        List<List<Integer>> graph;

        Graph(int n) {
            create(n);
        }

        void create(int n) {
            List<List<Integer>> graph = new ArrayList<>();
            for (int i = 0; i < n; i++) {
                graph.add(new ArrayList<>());
            }
            this.graph = graph;
        }

        void readBi(int m, FastScanner in) {
            for (int i = 0; i < m; i++) {
                int v = in.nextInt() - 1;
                int u = in.nextInt() - 1;
                graph.get(v).add(u);
                graph.get(u).add(v);
            }
        }
    }

    class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner(InputStream io) {
            br = new BufferedReader(new InputStreamReader(io));
        }

        public String line() {
            String result = "";
            try {
                result = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return result;
        }

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

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

        public int[] nextArray(int n) {
            int[] res = new int[n];
            for (int i = 0; i < n; i++) {
                res[i] = in.nextInt();
            }
            return res;
        }

        public long[] nextArrayL(int n) {
            long[] res = new long[n];
            for (int i = 0; i < n; i++) {
                res[i] = in.nextLong();
            }
            return res;
        }

        public Long[] nextArrayL2(int n) {
            Long[] res = new Long[n];
            for (int i = 0; i < n; i++) {
                res[i] = in.nextLong();
            }
            return res;
        }


        public Integer[] nextArray2(int n) {
            Integer[] res = new Integer[n];
            for (int i = 0; i < n; i++) {
                res[i] = in.nextInt();
            }
            return res;
        }

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

    }

    void run_t_tests() {
        int t = in.nextInt();
        int i = 0;
        while (t-- > 0) {
            solve(in, out, i++);
        }
    }

    void run_one() {
        solve(in, out, -1);
    }

    @Override
    public void run() {
        in = new FastScanner(System.in);
        out = new PrintWriter(System.out);
        if (use_n_tests) {
            run_t_tests();
        } else {
            run_one();
        }
        out.close();
    }

    static FastScanner in;
    static PrintWriter out;

    public static void main(String[] args) throws InterruptedException {
        Thread thread = new Thread(null, new Main(), "", stack_size);
        thread.start();
        thread.join();
    }
}