CF1552D.Array Differentiation

普及+/提高

通过率:0%

时间限制:1.00s

内存限制:256MB

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题目描述

You are given a sequence of nn integers a1, a2, …, ana_1, \, a_2, \, \dots, \, a_n.

Does there exist a sequence of nn integers b1, b2, …, bnb_1, \, b_2, \, \dots, \, b_n such that the following property holds?

  • For each 1≤i≤n1 \le i \le n, there exist two (not necessarily distinct) indices jj and kk (1≤j, k≤n1 \le j, \, k \le n) such that ai=bj−bka_i = b_j - b_k.

给你一个长度为 nn 的整数序列 a1, a2, …, ana_1, \, a_2, \, \dots, \, a_n。

是否存在一个长度为 nn 的整数序列 b1, b2, …, bnb_1, \, b_2, \, \dots, \, b_n,使得以下性质成立?

  • 对每个 1≤i≤n1 \le i \le n,均存在两个(不一定互异)下标 jj 和 kk(满足 1≤j, k≤n1 \le j, \, k \le n),使得 ai=bj−bka_i = b_j - b_k。

输入格式

The first line contains a single integer tt (1≤t≤201 \le t \le 20) — the number of test cases. Then tt test cases follow.

The first line of each test case contains one integer nn (1≤n≤101 \le n \le 10).

The second line of each test case contains the nn integers a1, …, ana_1, \, \dots, \, a_n (−105≤ai≤105-10^5 \le a_i \le 10^5).

第一行包含一个整数 tt(1≤t≤201 \le t \le 20)—— 表示测试用例的数量。随后是 tt 个测试用例。

每个测试用例的第一行包含一个整数 nn(1≤n≤101 \le n \le 10)。

每个测试用例的第二行包含 nn 个整数 a1, …, ana_1, \, \dots, \, a_n(−105≤ai≤105-10^5 \le a_i \le 10^5)。

输出格式

For each test case, output a line containing YES if a sequence b1, …, bnb_1, \, \dots, \, b_n satisfying the required property exists, and NO otherwise.

对于每个测试用例,如果存在满足要求性质的序列 b1, …, bnb_1, \, \dots, \, b_n,则输出一行 YES;否则输出 NO。

输入输出样例

  • 输入#1

    5
    5
    4 -7 -1 5 10
    1
    0
    3
    1 10 100
    4
    -3 2 10 2
    9
    25 -171 250 174 152 242 100 -205 -258

    输出#1

    YES
    YES
    NO
    YES
    YES

说明/提示

In the first test case, the sequence b=[−9, 2, 1, 3, −2]b = [-9, \, 2, \, 1, \, 3, \, -2] satisfies the property. Indeed, the following holds:

  • a1=4=2−(−2)=b2−b5a_1 = 4 = 2 - (-2) = b_2 - b_5;
  • a2=−7=−9−(−2)=b1−b5a_2 = -7 = -9 - (-2) = b_1 - b_5;
  • a3=−1=1−2=b3−b2a_3 = -1 = 1 - 2 = b_3 - b_2;
  • a4=5=3−(−2)=b4−b5a_4 = 5 = 3 - (-2) = b_4 - b_5;
  • a5=10=1−(−9)=b3−b1a_5 = 10 = 1 - (-9) = b_3 - b_1.

In the second test case, it is sufficient to choose b=[0]b = [0], since a1=0=0−0=b1−b1a_1 = 0 = 0 - 0 = b_1 - b_1.

In the third test case, it is possible to show that no sequence bb of length 33 satisfies the property.

在第一个测试用例中,序列 b=[−9, 2, 1, 3, −2]b = [-9, \, 2, \, 1, \, 3, \, -2] 满足该性质。事实上,以下等式成立:

  • a1=4=2−(−2)=b2−b5a_1 = 4 = 2 - (-2) = b_2 - b_5;
  • a2=−7=−9−(−2)=b1−b5a_2 = -7 = -9 - (-2) = b_1 - b_5;
  • a3=−1=1−2=b3−b2a_3 = -1 = 1 - 2 = b_3 - b_2;
  • a4=5=3−(−2)=b4−b5a_4 = 5 = 3 - (-2) = b_4 - b_5;
  • a5=10=1−(−9)=b3−b1a_5 = 10 = 1 - (-9) = b_3 - b_1。

在第二个测试用例中,只需选择 b=[0]b = [0] 即可,因为 a1=0=0−0=b1−b1a_1 = 0 = 0 - 0 = b_1 - b_1。

在第三个测试用例中,可以证明:不存在长度为 33 的序列 bb 满足该性质。

输入解题思路,AI测评打分。不知道怎么写?

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