javascript - access to elements of an array in js vs hashtable in c++ or c# performance? -


js uses hash table access elements of array. slower method of accessing array elements in c++ or c# languages?

var arr=[]; arr[0]=23; arr[1]=12; arr['2tr5']=54;

is algorithm accesses elements of array in js same hashtable in c++ or c#? how can speed access elements directly , why doesn't js use dense array fast access elements.


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