Problems
Ladders
Ladders
Ladder is a set of cubes in which each over the top layer contains fewer blocks than the previous one.
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Count the number of ladders that can be built from \textbf{n }blocks.
\InputFile
One integer \textbf{n }(\textbf{1 }≤ \textbf{n }≤ \textbf{100}).
\OutputFile
Print the required number of ladders.
Input example #1
3
Output example #1
2