Triangle and fix of issue#19#21

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smh0109 wants to merge 5 commits intocduck:masterfrom

smh0109:triangle

Commits on Jan 30, 2022

Commits on Jan 31, 2022

fixed bug in Triangle.isDeltaslim()
smh0109
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Commits on Feb 5, 2022

added surroundingIdealTriangle(self) and neigbourhood(self, delta, edgeNum=0)
smh0109
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Commits on Feb 13, 2022

Updated Triangle.py
smh0109
committed