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Twice the ruler / Twice the ruler

Twice the ruler
Twice the ruler

therulerproblem of two parts,connected bydovetail.Twice thelengthofa rulercan drawthe line,The mainsolution todrawthe linebeyondthe length of therulerproblem.Whenthe length ofthe lineexceeds theruler,slidingpart,tickthe0pointon the scaleneeded forthe other part,todrawto the end.


Nanjing Forestry University

Nanjing Forestry University
Nanjing, China