- Don't depend on just loops (either for or while),
- check actual loop variables whether they are incremented, decremened, multiplied, divided...
- For linked list, check how much pointer points to elements ?
- For stacks, queues, dequeus, how many elements are atmost procesed inside these ?
- For trees and graphs : how many atmost nodes are procesed ?
- For strings, arrays similar to linked list, how many times we are traversing to each one of those elements, or how much our pointer points to ?