AtCoder Regular Contest 202 (Div. 1)
A
Merge and Increment
AtCoder
⌀ 1691
原题
←B →
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Problem Statement

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An integer sequence that satisfies the following condition is called a good sequence.

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  • It is possible to perform the following merge operation zero or more times to make the sequence length $1$.
  • Choose a location where two consecutive elements have equal values. Let $x$ be the value of those elements. Remove both elements and insert $x+1$ at the location where the elements were. For example, if we perform a merge operation on the 2nd and 3rd elements of the sequence $(1, 3, 3, 5)$, the sequence after the operation will be $(1, 4, 5)$.
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There is a length-$N$ integer sequence $A = (A_1, A_2, \dots, A_N)$. You can perform the following insertion operation zero or more times.

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  • Choose any integer $x$. Insert one $x$ at any position in $A$ (possibly the beginning or end).
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What is the minimum number of insertion operations needed to make $A$ a good sequence? For any $N$ and $A$ satisfying the constraints, it is possible to make $A$ a good sequence with a finite number of insertion operations.

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You are given $T$ test cases; solve the problem for each of them.

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Constraints

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  • $1 \leq T \leq 2 \times 10^5$
  • $1 \leq N \leq 2 \times 10^5$
  • $1 \leq A_i \leq 10^9$
  • The sum of $N$ over all test cases is at most $2 \times 10^5$.
  • All input values are integers.
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Input

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The input is given from Standard Input in the following format. Here, $\mathrm{case}_i$ means the $i$-th test case.

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T
\mathrm{case}_1
\mathrm{case}_2
\vdots
\mathrm{case}_T

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Each test case is given in the following format:

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N
A_1 A_2 \dots A_N

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Output

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Output $T$ lines. The $i$-th line should contain the answer for the $i$-th test case. For each test case, output the minimum number of insertion operations needed to make $A$ a good sequence.

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样例

Input #1
4
3
4 2 2
1
1
5
1 3 5 4 2
10
766294630 440423914 59187620 725560241 585990757 965580536 623321126 550925214 122410709 549392045
Output #1
1
0
6
1889132222
For the 1st test case, the sequence $(4, 2, 2, 3)$ obtained by inserting $3$ at the end of $A$ is a good sequence because it can be reduced to length $1$ by performing merge operations in the following steps. - Remove the $2$s at the 2nd and 3rd positions and insert $2+1=3$. The sequence becomes $(4, 3, 3)$. - Remove the $3$s at the 2nd and 3rd positions and insert $3+1=4$. The sequence becomes $(4, 4)$. - Remove the $4$s at the 1st and 2nd positions and insert $4+1=5$. The sequence becomes $(5)$. It is impossible to make $A$ a good sequence with fewer than one insertion operation, so the answer is $1$.
题目信息
题号
arc202_a
时间限制
2 s
内存限制
1024 MB

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