https://www.hackerrank.com/challenges/sparse-arrays/leaderboard?page=8
Sparse Arrays - Leaderboard | HackerRank
Determine the number of times a string has previously appeared.
sparse arraysleaderboardhackerrank
https://eslint.org/docs/v8.x/rules/no-sparse-arrays
no-sparse-arrays - ESLint - Pluggable JavaScript Linter
A pluggable and configurable linter tool for identifying and reporting on patterns in JavaScript. Maintain your code quality with ease.
sparse arrayseslintpluggablejavascriptlinter