You are given an array of intervals intervals, where intervals[i] = [start_i, end_i] represents an inclusive interval starting at $ ext{start}_i$ and ending at $ ext{end}_i$.

Two intervals intersect if they share at least $1$ common point.

Return the total number of pairs $(i, j)$ with $0 \le i < j < ext{intervals.length}$ such that intervals[i] and intervals[j] intersect.

Constraints:

• $2 \le n ==$ intervals.length $\le 10^5$

• intervals[i] = [start_i, end_i]

• $0 \le ext{start}_i \le ext{end}_i \le 10^9$

Now, let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.

Implement your solution in the following coding playground.