1734 Select Three Sticks
Hazrat Ali
You are given nn sticks with positive integral length a1,a2,…,ana1,a2,…,an.
You can perform the following operation any number of times (possibly zero):
- choose one stick, then either increase or decrease its length by 11. After each operation, all sticks should have positive lengths.
What is the minimum number of operations that you have to perform such that it is possible to select three of the nn sticks and use them without breaking to form an equilateral triangle?
An equilateral triangle is a triangle where all of its three sides have the same length.
The first line of the input contains a single integer tt (1≤t≤1001≤t≤100) — the number of test cases. The description of the test cases follows.
The first line of each test case contains a single integer nn (3≤n≤3003≤n≤300) — the number of sticks.
The second line of each test case contains nn integers a1,a2,…,ana1,a2,…,an (1≤ai≤1091≤ai≤109) — the lengths of the sticks.
It is guaranteed that the sum of nn over all test cases does not exceed 300300.
For each test case, print one integer on a single line — the minimum number of operations to be made.
2 4 1 1
In the first test case, you can increase the length of the first stick by 11, then decrease the length of the third stick by 11. In total, you perform 22 operations, such that the three sticks form an equilateral triangle of side length 22.
In the fourth test case, you can decrease the length of the seventh stick by 11. An equilateral triangle of side length 11 can be selected and formed by the second, fourth, and seventh sticks.
Solution :