Hash table runtime complexity (insert, search and delete)

Hash tables are O(1) average and amortized case complexity, however it suffers from O(n) worst case time complexity. [And I think this is where your confusion is] Hash tables suffer from O(n) worst time complexity due to two reasons: If too many elements were hashed into the same key: looking inside this key may take O(n) time. Once a hash table has passed its load balance – it has …

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How to calculate time complexity of backtracking algorithm?

In short: Hamiltonian cycle : O(N!) in the worst case WordBreak and StringSegment : O(2^N) NQueens : O(N!) Note: For WordBreak there is an O(N^2) dynamic programming solution. More details: In Hamiltonian cycle, in each recursive call one of the remaining vertices is selected in the worst case. In each recursive call the branch factor decreases by 1. Recursion …

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What is the time complexity of while loops?

When you gotta do something n times, you have to do it n times. You can use a for loop, a while loop or whatever that your programming language (or pseudo code!) offers. Crudely, big O notation comments on the amount of work you have to do, and doesn’t care about how you do it …

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