hdu 2602 Bone Collector 01背包

Bone Collector

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 17590    Accepted Submission(s): 6954


Problem Description
Many years ago , in Teddy’s hometown there was a man who was called “Bone Collector”. This man like to collect varies of bones , such as dog’s , cow’s , also he went to the grave …
The bone collector had a big bag with a volume of V ,and along his trip of collecting there are a lot of bones , obviously , different bone has different value and different volume, now given the each bone’s value along his trip , can you calculate out the maximum of the total value the bone collector can get ?
 
Input
The first line contain a integer T , the number of cases.
Followed by T cases , each case three lines , the first line contain two integer N , V, (N <= 1000 , V <= 1000 )representing the number of bones and the volume of his bag. And the second line contain N integers representing the value of each bone. The third line contain N integers representing the volume of each bone.
 
Output
One integer per line representing the maximum of the total value (this number will be less than 231).
 
Sample Input
1 5 10 1 2 3 4 5 5 4 3 2 1
 
Sample Output
14
 
最近比较忙,在看01背包,也不知道为什么,好久不做题了,似乎什么也不会,01背包的一维的优化怎么也看不懂,今天看了一个博客,画了一个表,终于明白了。菜鸟还要努力啊!搞ACM这么长时间连个动态规划还处于入门阶段……
 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstdlib>
 4 #include <cstring>
 5 #include <algorithm>
 6 using namespace std;
 7 int main(void){
 8 #ifndef ONLINE_JUDGE
 9   freopen("2602.in", "r", stdin);
10 #endif
11   const int N = 1000+10;
12   int t, n, V, w[N], c[N], f[N];
13   scanf("%d", &t);
14   while (t--){
15     scanf("%d%d", &n, &V);
16     for (int i = 1; i <= n; ++i) scanf("%d", w+i);
17     for (int i = 1; i <= n; ++i) scanf("%d", c+i);
18     memset(f, 0, sizeof(f));
19     for (int i = 1; i <= n; ++i){
20       for (int v = V; v >= c[i]; --v){
21         f[v] = max(f[v], f[v-c[i]] + w[i]);
22       }
23     }
24     printf("%d\n", f[V]);
25   }
26   return 0;
27 }

引用一个博客,用于理解01背包,尤其是那个图表,自己画一遍,就基本理解为什么可以优化成一维数组了!

http://www.wutianqi.com/?p=539

原文地址:https://www.cnblogs.com/liuxueyang/p/2986189.html