120 lines
1.9 KiB
Markdown
120 lines
1.9 KiB
Markdown
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# D. Find the Different Ones!
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[Codeforces.com](https://codeforces.com/contest/1927/problem/D)
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You are given an array a of n integers, and q queries.
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Each query is represented by two integers l
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and r (1≤l≤r≤n). Your task is to find, for each query, two indices i and j (or determine that they do not exist) such that:
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- l ≤ i ≤ r
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- l ≤ j ≤ r
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- ai ≠ aj
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In other words, for each query, you need to find a pair of different elements among al,al+1,…,ar, or report that such a pair does not exist.
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## Input
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The first line of the input contains a single integer t
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(1≤t≤104) — the number of test cases. The descriptions of the test cases follow.
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The first line of each test case contains a single integer n
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(2≤n≤2⋅105) — the length of the array a.
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The second line of each test case contains n
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integers a1,a2,…,an (1≤ai≤106) — the elements of the array a.
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The third line of each test case contains a single integer q
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(1≤q≤2⋅105) — the number of queries.
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The next q lines contain two integers each, l and r (1≤l<r≤n) — the boundaries of the query.
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It is guaranteed that the sum of the values of n across all test cases does not exceed 2⋅105. Similarly, it is guaranteed that the sum of the values of q across all test cases does not exceed 2⋅105.
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## Output
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For each query, output two integers separated by space: i and j (l≤i,j≤r), for which ai≠aj. If such a pair does not exist, output i=−1 and j=−1.
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You may separate the outputs for the test cases with empty lines. This is not a mandatory requirement.
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## Example
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Input
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```
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5
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5
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1 1 2 1 1
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3
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1 5
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1 2
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1 3
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6
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30 20 20 10 10 20
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5
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1 2
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2 3
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2 4
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2 6
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3 5
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4
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5 2 3 4
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4
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1 2
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1 4
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2 3
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2 4
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5
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1 4 3 2 4
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5
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1 5
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2 4
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3 4
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3 5
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4 5
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5
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2 3 1 4 2
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7
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1 2
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1 4
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1 5
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2 4
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2 5
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3 5
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4 5
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```
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Output
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```
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2 3
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-1 -1
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1 3
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2 1
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-1 -1
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4 2
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4 6
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5 3
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1 2
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1 2
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2 3
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3 2
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1 3
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2 4
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3 4
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5 3
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5 4
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1 2
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4 2
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1 3
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2 3
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3 2
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5 4
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5 4
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```
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