Find Plateaus in a Sequence

You are given a sequence of n integers representing the heights at consecutive points. A plateau is defined as a contiguous subsequence where the height remains constant for at least two consecutive points. Your task is to find all plateaus in the sequence and output the starting and ending indices (1-indexed) of each plateau.

If there is no plateau in the sequence, output the string No Plateaus.

Note: The indices in the output are 1-indexed.

inputFormat

Input is read from standard input (stdin). The first line contains an integer n representing the number of points. The second line contains n space-separated integers representing the heights.

outputFormat

If one or more plateaus are found, output each plateau on a new line with two space-separated integers denoting the start and end indices of that plateau. If no plateaus are found, output No Plateaus.

## sample

10
1 2 2 2 3 4 4 2 2 1

2 4
6 7
8 9

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