Medium questions combine two ideas: a loop plus a dictionary, a stack, a sort with a tie-break, or a running value carried through the data.
Before coding, explain your plan in one or two sentences and state its complexity. Interviewers care about that conversation as much as the code. Then write it, and walk through one example by hand, including an edge case.
About ten minutes per question is a good pace. Each one is checked on the example in the prompt and on hidden inputs: empty data, ties, values that never change, and the case that breaks the obvious first idea.