Codeforces Round 887 (Div. 2)
A
Desorting
Codeforces
800
原题
←B →
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Call an array $a$ of length $n$ sorted if $a_1 \leq a_2 \leq \ldots \leq a_{n-1} \leq a_n$.

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Ntarsis has an array $a$ of length $n$.

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He is allowed to perform one type of operation on it (zero or more times):

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  • Choose an index $i$ ($1 \leq i \leq n-1$).
  • Add $1$ to $a_1, a_2, \ldots, a_i$.
  • Subtract $1$ from $a_{i+1}, a_{i+2}, \ldots, a_n$.
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The values of $a$ can be negative after an operation.

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Determine the minimum operations needed to make $a$ not sorted.

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Input

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Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 100$). The description of the test cases follows.

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The first line of each test case contains a single integer $n$ ($2 \leq n \leq 500$) — the length of the array $a$.

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The next line contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \leq a_i \leq 10^9$) — the values of array $a$.

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It is guaranteed that the sum of $n$ across all test cases does not exceed $500$.

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Output

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Output the minimum number of operations needed to make the array not sorted.

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Note

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In the first case, we can perform $1$ operation to make the array not sorted:

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  • Pick $i = 1$. The array $a$ then becomes $[2, 0]$, which is not sorted.
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In the second case, we can perform $2$ operations to make the array not sorted:

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  • Pick $i = 3$. The array $a$ then becomes $[2, 9, 11, 12]$.
  • Pick $i = 3$. The array $a$ then becomes $[3, 10, 12, 11]$, which is not sorted.
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It can be proven that $1$ and $2$ operations are the minimal numbers of operations in the first and second test cases, respectively.

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In the third case, the array is already not sorted, so we perform $0$ operations.

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样例

Input #1
4
2
1 1
4
1 8 10 13
3
1 3 2
3
1 9 14
Output #1
1
2
0
3
InputCopy OutputCopy
题目信息
题号
1853A
时间限制
1 s
内存限制
256 MB
标签
暴力
贪心
数学

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