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So, anyone can tell me this:

When the input is(for example):

1
2.0 2.0 4.0 2.0 1.0

The output has to be:

1
-inf +inf 1.000

or can be:

3
-inf 2.000 1.000
2.000 4.000 1.000
4.000 +inf 1.000