Please someone explain the second case or subtask and what is the use of that formula in the editorial sol

[wrango]

ZCO13001 - Editorial

PROBLEM SETTER - ZCO 2013 DIFFICULTY – Easy PREREQUISITES – Sorting FIRST SUBTASK SOLUTION – A simple brute for iterating on all the C(N,2) combinations can do the task easily for N<5000, by taking the sum of difference of all pairs of elements. int ans=0; for(int i = 1;i < n+1;i++) for(int j = i+1;j < n+1;j++) answer += abs(a[j]-a[i]); cout << answer; TIME COMPLEXITY - O(N^2) KEY OBSERVATIONS – Sorting the array will not cause any change to the answer as the answer does not dep…