CF1851D.Prefix Permutation Sums

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题目描述

Your friends have an array of nn elements, calculated its array of prefix sums and passed it to you, accidentally losing one element during the transfer. Your task is to find out if the given array can matches permutation.

A permutation of nn elements is an array of nn numbers from 11 to nn such that each number occurs exactly one times in it.

The array of prefix sums of the array aa — is such an array bb that bi=j=1iaj,1inb_i = \sum_{j=1}^i a_j, 1 \le i \le n .

For example, the original permutation was [1,5,2,4,3][1, 5, 2, 4, 3] . Its array of prefix sums — [1,6,8,12,15][1, 6, 8, 12, 15] . Having lost one element, you can get, for example, arrays [6,8,12,15][6, 8, 12, 15] or [1,6,8,15][1, 6, 8, 15] .

It can also be shown that the array [1,2,100][1, 2, 100] does not correspond to any permutation.

输入格式

The first line contains a positive number tt ( 1t1041 \le t \le 10^4 ) — the number of test cases. The description of the test cases follows.

The first line of the description of each test case contains a positive number nn ( 2n21052 \le n \le 2 \cdot 10^5 ) — the size of the initial array.

The second line of the description of each test case contains n1n - 1 positive number aia_i ( 1ai10181 \le a_i \le 10^{18} ), ai1<aia_{i-1} < a_i — elements of the array of prefix sums.

It is guaranteed that the sum of nn over all test cases does not exceed 21052 \cdot 10^5 .

输出格式

For each test case, output "YES" if such a permutation exists, and "NO" otherwise.

You can output "YES" and "NO" in any case (for example, the strings "yEs", "yes" and "Yes" will be recognized as a positive response).

输入输出样例

  • 输入#1

    12
    5
    6 8 12 15
    5
    1 6 8 15
    4
    1 2 100
    4
    1 3 6
    2
    2
    3
    1 2
    4
    3 7 10
    5
    5 44 46 50
    4
    1 9 10
    5
    13 21 36 42
    5
    1 2 3 1000000000000000000
    9
    9 11 12 20 25 28 30 33

    输出#1

    YES
    YES
    NO
    YES
    YES
    NO
    YES
    NO
    NO
    NO
    NO
    NO

说明/提示

In the fourth example, for example, the permutation [1,2,3,4][1, 2, 3, 4] is suitable. In the fifth example, for example, the permutation [2,1][2, 1] is suitable. In the seventh example, for example, the permutation [1,2,4,3][1, 2, 4, 3] is suitable.

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