Arithmetic Sequence

AtCoder

IDarc123_a

Time2000ms

Memory256MB

Difficulty—

Given is a sequence of three integers $A = (A_1, A_2, A_3)$. On this sequence, you can do the following operation any number of times: * choose $i\in {1,2,3}$ and add $1$ to $A_i$. Find the minimum number of operations needed to make $A$ arithmetic. Here, the sequence $A = (A_1, A_2, A_3)$ is arithmetic when $A_2 - A_1 = A_3 - A_2$ holds. ## Constraints * $1\leq A_1, A_2, A_3\leq 10^{15}$ ## Input Input is given from Standard Input in the following format: $A_1$ $A_2$ $A_3$ [samples]

Samples

Input #1

4 8 10

Output #1

2

One operation with $i = 1$ and then one operation with $i = 3$ yield an arithmetic sequence $(5, 8, 11)$.

Input #2

10 3 4

Output #2

4

Four operations with $i = 2$ yield an arithmetic sequence $(10, 7, 4)$.

Input #3

1 2 3

Output #3

0

The sequence $A$ is already arithmetic from the beginning, so we need zero operations.

Input #4

1000000000000000 1 1000000000000000

Output #4

999999999999999

API Response (JSON)

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    "name": "Arithmetic Sequence",
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      "content": "Given is a sequence of three integers $A = (A_1, A_2, A_3)$. On this sequence, you can do the following operation any number of times: *   choose $i\\in {1,2,3}$ and add $1$ to $A_i$. Find the minimu",
      "description_type": "Markdown"
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      "memory_limit": 262144
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    "difficulty": "None",
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  "statements": [
    {
      "statement_type": "Markdown",
      "content": "Given is a sequence of three integers $A = (A_1, A_2, A_3)$. On this sequence, you can do the following operation any number of times:\n\n*   choose $i\\in {1,2,3}$ and add $1$ to $A_i$.\n\nFind the minimu...",
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