hdu5115 Dire Wolf 区间DP

Dire Wolf

Time Limit: 5000/5000 MS (Java/Others)    Memory Limit: 512000/512000 K (Java/Others)
Total Submission(s): 2178    Accepted Submission(s): 1260

Problem Description

Dire wolves, also known as Dark wolves, are extraordinarily large and powerful wolves. Many, if not all, Dire Wolves appear to originate from Draenor.
Dire wolves look like normal wolves, but these creatures are of nearly twice the size. These powerful beasts, 8 - 9 feet long and weighing 600 - 800 pounds, are the most well-known orc mounts. As tall as a man, these great wolves have long tusked jaws that look like they could snap an iron bar. They have burning red eyes. Dire wolves are mottled gray or black in color. Dire wolves thrive in the northern regions of Kalimdor and in Mulgore.
Dire wolves are efficient pack hunters that kill anything they catch. They prefer to attack in packs, surrounding and flanking a foe when they can.
— Wowpedia, Your wiki guide to the World of Warcra

Matt, an adventurer from the Eastern Kingdoms, meets a pack of dire wolves. There are N wolves standing in a row (numbered with 1 to N from left to right). Matt has to defeat all of them to survive.

Once Matt defeats a dire wolf, he will take some damage which is equal to the wolf’s current attack. As gregarious beasts, each dire wolf i can increase its adjacent wolves’ attack by b_i. Thus, each dire wolf i’s current attack consists of two parts, its basic attack ai and the extra attack provided by the current adjacent wolves. The increase of attack is temporary. Once a wolf is defeated, its adjacent wolves will no longer get extra attack from it. However, these two wolves (if exist) will become adjacent to each other now.

For example, suppose there are 3 dire wolves standing in a row, whose basic attacks ai are (3, 5, 7), respectively. The extra attacks b_i they can provide are (8, 2, 0). Thus, the current attacks of them are (5, 13, 9). If Matt defeats the second wolf first, he will get 13 points of damage and the alive wolves’ current attacks become (3, 15).

As an alert and resourceful adventurer, Matt can decide the order of the dire wolves he defeats. Therefore, he wants to know the least damage he has to take to defeat all the wolves.

 

Input

The first line contains only one integer T , which indicates the number of test cases. For each test case, the first line contains only one integer N (2 ≤ N ≤ 200).

The second line contains N integers a_i (0 ≤ a_i ≤ 100000), denoting the basic attack of each dire wolf.

The third line contains N integers b_i (0 ≤ b_i ≤ 50000), denoting the extra attack each dire wolf can provide.

 

Output

For each test case, output a single line “Case #x: y”, where x is the case number (starting from 1), y is the least damage Matt needs to take.

 

Sample Input

2
3
3 5 7
8 2 0
10
1 3 5 7 9 2 4 6 8 10
9 4 1 2 1 2 1 4 5 1

 

Sample Output

Case #1: 17
Case #2: 74

Hint
In the first sample, Matt defeats the dire wolves from left to right. He takes 5 + 5 + 7 = 17 points of damage which is the least damage he has to take.

dp[i][j] = min(dp[i][j], dp[i][k - 1] + dp[k + 1][j] + a[k] + b[i - 1] + b[j + 1])

区间[i, j]的伤害为先杀k左面dp[i][k - 1]，其中算上了k的附加伤害；再杀k右面dp[k + 1][j]，其中也算上了k的附加伤害；最后杀k，注意由于之前杀了[i, k - 1]和[k + 1, j]，该杀k的时候，k的两边现在是i - 1和j + 1，所以最后杀k的伤害是a[k] + b[i - 1] + b[j + 1]

#include <cstdio>
#include <algorithm>
#include <iostream>
#include <cstring>

using namespace std;

const int maxn = 200, INF = 0x3f3f3f3f;

int T, N, kase;
int a[maxn + 5], b[maxn + 5], dp[maxn + 5][maxn + 5];

int main()
{
	kase = 0;
	scanf("%d", &T);
	while (T--) {
		scanf("%d", &N);
		for (int i = 1; i <= N; i++) {
			scanf("%d", a + i);
		}
		for (int i = 1; i <= N; i++) {
			scanf("%d", b + i);
		}
		for (int len = 1; len <= N; len++) {
			for (int i = 1; i <= N; i++) {
				int j = i + len - 1;
				if (j <= N) {
					dp[i][j] = INF;
					for (int k = i; k <= j; k++) {
						dp[i][j] = min(dp[i][j], dp[i][k - 1] + dp[k + 1][j] + a[k] + b[i - 1] + b[j + 1]);
					}
				}
			}
		}
		printf("Case #%d: %d\n", ++kase, dp[1][N]);
	}
	return 0;
}