array javascript time complexity

[blade-sensei]

• Access - O(1)
• Appending - Amortized O(1) (sometimes resizing the hashtable is required; usually only insertion is required)
• Prepending - O(n) via unshift, since it requires reassigning all the indexes
• Insertion - Amortized O(1) if the value does not exist. O(n) if you want to shift existing values (Eg, using splice).
• Deletion - Amortized O(1) to remove a value, O(n) if you want to reassign indices via splice.
• Swapping - O(1)

[blade-sensei]

https://stackoverflow.com/questions/11514308/big-o-of-javascript-arrays