c# - Stack constructor - What to put as initial capacity? -


one of constructors shown on msdn, takes int32 parameter representing initial capacity.

there remark on above documentation page states following:

if count less capacity of stack, push o(1) operation. if capacity needs increased accommodate new element, push becomes o(n) operation, n count. pop o(1) operation.

i'm in situation don't know how initial capacity give stack. better overestimate think need ? because surely low initial capacity make performance suffer?

what drawback in passing in high initial capacity in terms of performance?

internally, storage array inside stack<t> grows exponentially, implies amortized o(1) cost add element. so, if don't know correct initial capacity, don't worry , use default constructor, performance anyway.


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