javascript - Check if the value in array in efficiently -


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my goal find if value in javascript array, efficiently. understand inarray? check execute in o(n) n length of array because have traverse through every variable in array. hashmap return value in 0(1) (at least understanding)

so if instead of traversing array created key -> variable association, key identical value , tried getting element key. if exists, return true, if 'undefined', return false?

has ever done before , feasible in terms of javascript language?


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