P9483 [NOI2023] Merging Books
Description
Xiao C has $n$ books, each with a weight. He decides to merge them into one pile.
In each merge, Xiao C can put one pile of books on top of another pile, so that they become one pile. If Xiao C puts the $i$-th pile onto the $j$-th pile, the stamina cost is **the weight of the $i$-th pile** plus **the sum of the wear values of the two piles**.
Initially, each book forms its own pile and all wear values are $0$. Each time Xiao C merges two piles, the new pile’s wear value becomes **twice the larger wear value of the two piles plus one**, and its weight becomes **the sum of the weights of the two piles**.
Your task is to design the merging order to minimize Xiao C’s stamina cost, and output this minimum cost.
Input Format
**This problem has multiple test cases.**
The first line contains a positive integer $t$, the number of test cases.
Then for each test case:
The first line contains a positive integer $n$, meaning there are $n$ books.
The second line contains $n$ positive integers; the $i$-th number $w_i$ is the weight of the $i$-th book.
Output Format
For each test case, output one integer per line, representing the minimum stamina required to merge the $n$ books into one pile.
Explanation/Hint
**[Sample Explanation #1]**
If Xiao C first merges the $4$ books in pairs, and then merges the two resulting piles into one pile, then the stamina costs of the first two merges are both $1$. For the third merge, he puts a pile of weight $2$ onto the other pile; both piles have wear value $1$, so the stamina cost is $2 + 1 + 1 = 4$.
Therefore, under this plan, Xiao C’s total stamina cost is only $1 + 1 + 4 = 6$.
It can be proven that, in the above example, $6$ is the minimum stamina cost.
**[Constraints]**
For all test cases: $1 \le t \le 10$, $1 \le n \le 100$, $1 \le w_i \le 10 ^ 9$.
|Test Point ID|$n \le$|Special Property|
|:-:|:-:|:-:|
|$1 \sim 2$|$7$|No|
|$3$|$11$|No|
|$4$|$13$|No|
|$5 \sim 6$|$22$|No|
|$7 \sim 8$|$28$|No|
|$9 \sim 13$|$50$|No|
|$14$|$60$|No|
|$15$|$70$|No|
|$16$|$80$|No|
|$17 \sim 18$|$100$|Yes|
|$19 \sim 20$|$100$|No|
Special property: it is guaranteed that $w_i = 1$.
Translated by ChatGPT 5