Find top countries by population per continent

You are given a table called world_population. Every row stores one country's most recent population count, split across three columns: continent (VARCHAR), country (VARCHAR) and population (BIGINT). No two rows share the same continent together with the same country. The interviewer walks through three progressively harder questions: Report the single most populous country of every continent, outputting continent, country and population. Follow-up: report the two most…