I think this question is ambiguous.
Considering this question, 2 design of staircase is possible
1)
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2)
Ladder – based staircase.
- In 1), both the statement are necessary
- In 2), Only first statement is sufficient.
Be it 1) or 2), in both the cases, we are making assumptions.
NOTE: There can other deigns of staircase too! :) Something like this …
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