javascript - What's the time complexity of array.splice() in Google Chrome? -

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if remove 1 element array using splice() so:

arr.splice(i, 1);

will o(n) in worst case because shifts elements after i? or constant time, linked list magic underneath?

worst case should o(n) (copying n-1 elements new array).

a linked list o(1) single deletion.

for interested i've made lazily-crafted benchmark. (please don't run on windows xp/vista). as can see though, looks constant (i.e. o(1)), knows they're doing behind scenes make crazy-fast. note regardless, actual splice fast.

rerunning extended benchmark directly in v8 shell suggest o(n). note though need huge array sizes runtime that's affect code. should expected if @ v8 code uses memmove create new array.


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