Codeforces Round 800 (Div. 2)
C
Directional Increase
Codeforces
未评级
原题
← BD →
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We have an array of length $n$. Initially, each element is equal to $0$ and there is a pointer located on the first element.

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We can do the following two kinds of operations any number of times (possibly zero) in any order:

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  1. If the pointer is not on the last element, increase the element the pointer is currently on by $1$. Then move it to the next element.
  2. If the pointer is not on the first element, decrease the element the pointer is currently on by $1$. Then move it to the previous element.
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But there is one additional rule. After we are done, the pointer has to be on the first element.

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You are given an array $a$. Determine whether it's possible to obtain $a$ after some operations or not.

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Input

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The first line contains a single integer $t$ $(1\le t\le 1000)$  — the number of test cases. The description of the test cases follows.

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The first line of each test case contains a single integer $n$ $(1\le n\le 2 \cdot 10^5)$  — the size of array $a$.

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The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($-10^9 \le a_i \le 10^9$) — elements of the array.

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It is guaranteed that the sum of $n$ over all test cases doesn't exceed $2 \cdot 10^5$.

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Output

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For each test case, print "Yes" (without quotes) if it's possible to obtain $a$ after some operations, and "No" (without quotes) otherwise.

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

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Note

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In the first test case we can obtain the array after some operations, but the pointer won't be on the first element.

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One way of obtaining the array in the second test case is shown below.

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$\langle \underline{0}, 0, 0, 0\rangle \to \langle 1, \underline{0}, 0, 0 \rangle \to \langle \underline{1}, -1, 0, 0\rangle \to \langle 2, \underline{-1}, 0, 0\rangle \to \langle 2, 0, \underline{0}, 0\rangle \to \langle 2, \underline{0}, -1, 0\rangle \to \langle \underline{2}, -1, -1, 0\rangle$

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样例

Input #1
7
2
1 0
4
2 -1 -1 0
4
1 -4 3 0
4
1 -1 1 -1
5
1 2 3 4 -10
7
2 -1 1 -2 0 0 0
1
0
Output #1
No
Yes
No
No
Yes
Yes
Yes
InputCopy OutputCopy
题目信息
题号
1694C
时间限制
1 s
内存限制
256 MB

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