luogu2871 [USACO07DEC]手链Charm Bracelet

题目描述

Bessie has gone to the mall's jewelry store and spies a charm bracelet. Of course, she'd like to fill it with the best charms possible from the N (1 ≤ N ≤ 3,402) available charms. Each charm i in the supplied list has a weight Wi (1 ≤ Wi ≤ 400), a 'desirability' factor Di (1 ≤ Di ≤ 100), and can be used at most once. Bessie can only support a charm bracelet whose weight is no more than M (1 ≤ M ≤ 12,880).

Given that weight limit as a constraint and a list of the charms with their weights and desirability rating, deduce the maximum possible sum of ratings.

有N件物品和一个容量为V的背包。第i件物品的重量是c[i]，价值是w[i]。求解将哪些物品装入背包可使这些物品的重量总和不超过背包容量，且价值总和最大。

输入输出格式

输入格式：

• Line 1: Two space-separated integers: N and M

• Lines 2..N+1: Line i+1 describes charm i with two space-separated integers: Wi and Di

输出格式：

• Line 1: A single integer that is the greatest sum of charm desirabilities that can be achieved given the weight constraints

输入输出样例

输入样例#1：

4 61 42 63 122 7

输出样例#1：

23

只能说翻译太强了…orz…

01背包都成入门级别的题辣

伪装成小学生水平毫不羞耻

#include<bits/stdc++.h>#define MAXN 1000001using namespace std;template <typename T> void read(T &x){x=0;int f=1;char ch=getchar();for(;!isdigit(ch);ch=getchar())if(ch=='-')f=-1;for(;isdigit(ch);ch=getchar())x=(x<<1)+(x<<3)+ch-'0';x*=f;}int f[MAXN];int c[MAXN],wei[MAXN];int main(){int n,v;read(n),read(v);for(int i=1;i<=n;++i) read(c[i]),read(wei[i]);for(int i=1;i<=n;++i)for(int j=v;j>=c[i];--j)f[j]=max(f[j],f[j-c[i]]+wei[i]);//for(int i=1;i<=v;++i) cout<<f[i]<<endl;printf("%d\n",f[v]); return 0;}