[MySQL/HackerRank] Population Density Difference

https://www.hackerrank.com/challenges/population-density-difference/problem?isFullScreen=true 

Population Density Difference | HackerRank

문제

Query the difference between the maximum and minimum populations in CITY.

Input Format

The CITY table is described as follows: 

Code

SELECT MAX(POPULATION) - MIN(POPULATION)
FROM CITY